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This study investigated monthly and annual reference evapotranspiration ETo changes over southwestern China (SWC) from 1960 to 2012, using the Food and Agriculture Organization of the United Nations' report 56 (FAO-56) Penman-Monteith equation and routine meteorological observations at 269 weather sites. During 1960-2012, the monthly and annual ETo decreased at most sites. Moreover, the SWC regional average trend in annual ETo was significantly negative (p < 0.05); this trend was the same in most months. A new separation method using several numerical experiments was proposed to quantify each driving factor's contribution to ETo changes and exhibited higher accuracy based on several validation criteria, after which an attribution analysis was performed. Across SWC, the declining annual ETo was mainly due to decreased net radiation (RN). Spatially, the annual ETo changes at most sites in eastern SWC (excluding southeastern West Guangxi) were generally due to RN, whereas wind speed (WND) or vapor pressure deficit (VPD) was the determinant at other sites. Nevertheless, the determinants differed among 12 months. For the whole SWC, increased VPD in February and decreased WND in April, May, and October were the determinant of decreased ETo; however, decreased RN was the determinant in other months. Overall, the determinant of the monthly ETo changes exhibited a complex spatial pattern. A complete analysis of ETo changes and the related physical mechanisms in SWC is necessary to better understand hydroclimatological extremes (e.g., droughts) and to develop appropriate strategies to sustain regional development (e.g., water resources and agriculture). Importantly, this separation method provides new perspective for quantitative attribution analyses and thus may be implemented in various scientific fields (e.g., climatology and hydrology). [ABSTRACT FROM AUTHOR]

Accurate detection and quantification of vegetation dynamics and drivers of observed climatic and anthropogenic change in space and time is fundamental for our understanding of the atmosphere-biosphere interactions at local and global scales. This case study examined the coupled spatial patterns of vegetation dynamics and climatic variabilities during the past three decades in the Upper Heihe River Basin (UHRB), a complex multiple use watershed in arid northwestern China. We apply empirical orthogonal function (EOF) and singular value decomposition (SVD) analysis to isolate and identify the spatial patterns of satellite-derived leaf area index (LAI) and their close relationship with the variability of an aridity index (AI = Precipitation/Potential Evapotranspiration). Results show that UHRB has become increasingly warm and wet during the past three decades. In general, the rise of air temperature and precipitation had a positive impact on mean LAI at the annual scale. At the monthly scale, LAI variations had a lagged response to climate. Two major coupled spatial change patterns explained 29% and 41% of the LAI dynamics during 1983-2000 and 2001-2010, respectively. The strongest connections between climate and LAI were found in the southwest part of the basin prior to 2000, but they shifted towards the north central area afterwards, suggesting that the sensitivity of LAI to climate varied over time, and that human disturbances might play an important role in altering LAI patterns. At the basin level, the positive effects of regional climate warming and precipitation increase as well as local ecological restoration efforts overwhelmed the negative effects of overgrazing. The study results offer insights about the coupled effects of climatic variability and grazing on ecosystem structure and functions at a watershed scale. Findings from this study are useful for land managers and policy makers to make better decisions in response to climate change in the study region. [ABSTRACT FROM AUTHOR]

Archaeamphora longicervia H. Q. Li was described as an herbaceous, Sarraceniaceaelike pitcher plant from the mid Early Cretaceous Yixian Formation of Liaoning Province, northeastern China. Here, a re-investigation of A. longicervia specimens from the Yixian Formation provides new insights into its identity and the morphology of pitcher plants claimed by Li. We demonstrate that putative pitchers of Archaeamphora are insectinduced leaf galls that consist of three components: (1) an innermost larval chamber; (2) an intermediate zone of nutritive tissue; and (3) an outermost wall of sclerenchyma. Archaeamphora is not a carnivorous, Sarraceniaceae-like angiosperm, but represents insect-galled leaves of the previously reported gymnosperm Liaoningocladus boii G. Sun et al. from the Yixian Formation. [ABSTRACT FROM AUTHOR]

A new species, Ginkgo huolinhensis sp. nov., with well-preserved cuticle from the Lower Cretaceous, Huolinhe Formation of Huolinhe Coal Field in Inner Mongolia, China, was studied morphologically and anatomically. The main characters of the new species are found in the leaves which are deeply dissected with narrow lobes, trichomes developed on both upper and lower epidermal cells, a media papilla developed on the periclinal walls for each cell in upper cuticle, and no trichomes on the cuticle of the petioles. These characters of G. huolinhensis sp. nov. distinguish from the known species of Ginkgo previously reported. This study of the new species is beneficial for the taxonomic research of fossil Ginkgo, and should be helpful for a better understanding the paleoenvironment of Ginkgo living in northeastern China during the Early Cretaceous. [ABSTRACT FROM AUTHOR]

The existence of the Cretaceous-Tertiary (K/T) boundary in the non-marine succession is expected at Jiayin in the Heilongjiang River area, China. Zircons from a tuff sample from the Baishantou Member of Wuyun Formation in Jiayin were analyzed by the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb dating and fission-track dating methods. Ages of 64.1±0.7 Ma (U-Pb) and 61.7±1.8 Ma (fission-track dating) were obtained, which allow re-evaluation of a previously reported late Maastrichian age for the tuff layer that was in conflict with the paleontological evidence. These results confirm the Danian age of the section in agreement with the paleontological evidence. [ABSTRACT FROM AUTHOR]

Aims Evapotranspiration (ET) is a key component of water balance and is closely linked to ecosystem productivity. In arid regions, large proportion of precipitation (PPT) is returned to the atmosphere through ET, with only a small amount available to plants. Our objective was to examine the variability in ET–soil water relationship based on a set of ecosystems that are representative for semi-arid Inner Mongolia and its main land use practices. Methods This study used Eddy covariance (EC) data of water vapor (i.e. ET, mm), PPT (mm), soil volumetric water content (VWC, %), root biomass density and soil properties from three paired sites in semi-arid Inner Mongolia: cropland (Cropland-D) versus undisturbed grassland (Steppe-D), grazed grassland (Grazed Steppe-X) versus fenced grassland (Fenced Steppe-X) and poplar plantation (Poplar-K) versus undisturbed shrubland (Shrubland-K). The paired sites experienced similar climate conditions and were equipped with the same monitoring systems. Important Findings The ET/PPT ratio was significantly lower at Cropland-D and Grazed Steppe-X in comparison to the undisturbed grasslands, Steppe-D and Fenced Steppe-X. These differences are in part explained by the lower VWC in the upper soil layers associated with compaction of surface soil in heavily grazed and fallow fields. In contrast, the ET/PPT ratio was much higher at the poplar plantation compared to the undisturbed shrubland because poplar roots tap groundwater. The VWC of different soil layers responded differently to rainfall events across the six study sites. Except for Poplar-K, ET was significantly constrained by VWC at the other five sites, although the correlation coefficients varied among soil layers. The relative contribution of soil water to ET correlated with the density of root biomass in the soil (R2 = 0.67, P < 0.01). The soil water storage in the upper 50 cm of soil contributed 59, 43, 64 and 23% of total water loss as ET at Steppe-D, Cropland-D, Shrubland-K and Poplar-K, respectively. Our across-site analysis indicates that the site level of soil water for ET differs between land use and land cover type due to altered root distribution and/or soil physical properties. As a result, we recommend that ecosystem models designed to predict the response of a wide variety of vegetation to climatic variation in arid regions include more detail in defining soil layers and interactions between evaporation, infiltration and root distribution patterns. [ABSTRACT FROM PUBLISHER]

The genus Czekanowskia is an important member of the Mesozoic flora and is widespread in the Northern Hemisphere. In China, it is found mostly in Late Triassic and Early and Middle Jurassic sediments of North China. With the exception of a few specimens, all the reports of this genus from China have been based on gross leaf morphology. Abundant Czekanowskia leaves, preserved as compression fossils, were collected from the Middle Jurassic, Zhaogou Formation of Inner Mongolia, China. In this article, two subgenera of Czekanowskia, Harrisella and Vachrameevia, are recognized from Inner Mongolia, China, on the basis of leaf morphology and epidermal characters. Two new species, Czekanowskia chinensis sp. nov. (subg. Harrisella) and Czekanowskia shiguaiensis sp. nov. (subg. Vachrameevia), are described. The occurrence of these species in the Middle Jurassic of Inner Mongolia significantly extends the stratigraphic and geographic distribution of Czekanowskia in the Northern Hemisphere. Analysis of the epidermal characters of material presented here along with consideration of other associated plants of the flora and sedimentology of the plant-bearing strata suggests that the two species described in this report grew in an area with a warm and humid climate in a warm temperate zone. Biostratigraphic correlation of the plant-bearing strata indicates that the specimens described here are Middle Jurassic in age. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the impact of the small proportional land use and land cover change (SPLULCC) on the water yield of a watershed in Loess Plateau, China. It discusses the significance of the precipitation regime in controlling hydrologic effects of soil conservation measures in a semi-arid environment. It further highlights the implication of climatic variability in assessing the effects of land use change and soil conservation measures on water yield.

The PRMS_Storm model was built as a storm event, distributed hydrological model for studying the hydrological effects of forest composition and spatial distribution on storm-flow volume and peakflow rates in the Xiangshuixi Watershed in the Three Gorges Reservoir Area, in the Yangtze River Basin in southwestern China. We developed three simulation scenarios based on forest composition and their spatial arrangements across the watershed, including all mixed conifer-evergreen broadleaf forests (Scenario 1), all mixed evergreen broadleaf forests (Scenario 2), and mixed conifer + evergreen broadleaf + shrub forests (Scenario 3). We examined 11 storm events observed during 2002-2005. Compared with the existing forest covers, modeling results suggested that the amount of overland flow was reduced by 21, 23, and 22%, and the interflow increased by 16, 88, and 30%, for Scenarios 1, 2, and 3, respectively. During the same time, peakflow rates were reduced by 20.8, 9.6, and 18.9%, respectively. The reduction of peakflow rates was most significant when rainfall intensity exceeded 0.8 mm/min and events with a short duration and effect was minor when rainfall intensity was below 0.5 mm/min. In general, we found that Scenarios 1 and 3 were preferred for reducing storm-flow volume and peakflow rates due to their higher interception rates, large soil water holding capacity, and higher soil infiltration capacity. The modeled results suggested soil properties are important in affecting the flow processes and thus forest composition and forest spatial distributions will affect storm-flow volume and peakflow rates at the watershed scale. To maximize flood reduction functions of a watershed, high priority should be given to those forest types (Scenarios 1 and 3) in reforestation practices in the study region. This study suggests both forest composition and spatial pattern are important reforestation designs for flood reduction in the Three Gorges Reservoir Area. [ABSTRACT FROM AUTHOR]

The relationship between forests and streamflows has long been an important research interest in China. The purpose of this paper is to summarize progress and lessons learned from the forest-streamflow studies over the past four decades in China. To better measure the research gaps between China and other parts of the world, a brief global review on the findings from paired watershed studies over the past 100 years was also provided. In China, forest management shifted in the later 1990s from timber harvesting to forest restoration. Forest-streamflow research was accordingly changed from assessing harvesting impacts to evaluating both harvesting and forestation effects. Over the past four decades, Chinese forest hydrology research has grown substantially. Significant progress has been made on measuring individual processes, but little solid, long-term data were available to assess the relationship between forest changes and streamflows because of an absence of standard paired watersheds. In addition, misuse of statistical analyses was often found in the literature. A unique opportunity exists in China to study the forestation effects on streamflow as several large-scale forestation programs are being implemented. Such an opportunity should include a robust paired watershed design under an integrated watershed ecosystem framework to avoid repeating the lessons already learned. Recommendations on future forest-streamflow research directions in China are provided. [ABSTRACT FROM AUTHOR]

Natural forests in southern China have been severely logged due to high human demand for timber, food, and fuels during the past century, but are recovering in the past decade. The objective of this study was to investigate how vegetation cover changes in composition and structure affected the water budgets of a 9.6-km2 Dakeng watershed located in a humid subtropical mountainous region in southern China. We analyzed 27 years (i.e., 1967-1993) of streamflow and climate data and associated vegetation cover change in the watershed. Land use/land cover census and Normalized Difference of Vegetation Index (NDVI) data derived from remote sensing were used to construct historic land cover change patterns. We found that over the period of record, annual streamflow ( Q) and runoff/precipitation ratio did not change significantly, nor did the climatic variables, including air temperature, Hamon’s potential evapotranspiration (ET), pan evaporation, sunshine hours, and radiation. However, annual ET estimated as the differences between P and Q showed a statistically significant increasing trend. Overall, the NDVI of the watershed had a significant increasing trend in the peak spring growing season. This study concluded that watershed ecosystem ET increased as the vegetation cover shifted from low stock forests to shrub and grasslands that had higher ET rates. A conceptual model was developed for the study watershed to describe the vegetation cover-streamflow relationships during a 50-year time frame. This paper highlighted the importance of eco-physiologically based studies in understanding transitory, nonstationary effects of deforestation or forestation on watershed water balances. [ABSTRACT FROM AUTHOR]

The Loess Plateau region in northwestern China has experienced severe water resource shortages due to the combined impacts of climate and land use changes and water resource exploitation during the past decades. This study was designed to examine the impacts of climatic variability on streamflow characteristics of a 12-km2 watershed near Tianshui City, Gansu Province in northwestern China. Statistic analytical methods including Kendall’s trend test and stepwise regression were used to detect trends in relationship between observed streamflow and climatic variables. Sensitivity analysis based on an evapotranspiration model was used to detect quantitative hydrologic sensitivity to climatic variability. We found that precipitation ( P), potential evapotranspiration (PET) and streamflow ( Q) were not statistically significantly different ( p > 0.05) over the study period between 1982 and 2003. Stepwise regression and sensitivity analysis all indicated that P was more influential than PET in affecting annual streamflow, but the similar relationship existed at the monthly scale. The sensitivity of streamflow response to variations of P and PET increased slightly with the increase in watershed dryness (PET/ P) as well as the increase in runoff ratio ( Q/ P). This study concluded that future changes in climate, precipitation in particular, will significantly impact water resources in the Loess Plateau region an area that is already experiencing a decreasing trend in water yield. [ABSTRACT FROM AUTHOR]

Quantifying the hydrologic responses to land use/land cover change and climate variability is essential for integrated sustainable watershed management in water limited regions such as the Loess Plateau in Northwestern China where an adaptive watershed management approach is being implemented. Traditional empirical modeling approach to quantifying the accumulated hydrologic effects of watershed management is limited due to its complex nature of soil and water conservation practices (e.g., biological, structural, and agricultural measures) in the region. Therefore, the objective of this study was to evaluate the ability of the distributed hydrologic model, MIKE SHE to simulate basin runoff. Streamflow data measured from an overland flow-dominant watershed (12 km2) in northwestern China were used for model evaluation. Model calibration and validation suggested that the model could capture the dominant runoff process of the small watershed. We found that the physically based model required calibration at appropriate scales and estimated model parameters were influenced by both temporal and spatial scales of input data. We concluded that the model was useful for understanding the rainfall-runoff mechanisms. However, more measured data with higher temporal resolution are needed to further test the model for regional applications. [ABSTRACT FROM AUTHOR]

During the Mesozoic era, Ginkgo leaves are diverse and widespread, especially in the Northern Hemisphere. Here we present three Ginkgo leaf types collected from the Middle Jurassic Zhaogou Formation of Shiguai coalbearing basin in Inner Mongolia, China. These are described for the first time on the basis of their leaf morphology and well-preserved cuticular characters. One new species, Ginkgo shiguaiensis, is described, and Ginkgo longifolius is recognized, while a third leaf type is designated as Ginkgo sp. The occurrence of these leaf types in the Middle Jurassic of Inner Mongolia significantly extends the stratigraphic and geographic distribution of Ginkgo in China. The associated plants, cuticular characters of the Ginkgo leaves, and the sedimentology of the plant-bearing strata suggest that these plants grew in a warm-temperate and moist climate. [ABSTRACT FROM AUTHOR]

The continuing study of early angiosperms from the Yixian Formation (≈125 Ma) of northeastern China has yielded a second early angiosperm genus. This report is a detailed account of this early flowering plant and recognizes earlier reports of similar fossils from Russia and China. Entire plants, including roots, stems, and branches terminating in fruits are presented and reconstructed. Evidence for a possible aquatic nature of this plant is presented. The relationship of Hyrcantha (‘Sinocarpus’) to the eudicots is discussed. The presence of this second early angiosperm genus, now known as a whole plant, is important in the discussion of its systematics and the ecology of the earliest angiosperms. [ABSTRACT FROM AUTHOR]

Examines globalization and cultural differences manifested within Chinese intellectual circles. Existence of misunderstanding in the midst of trans-cultural dialogue; Implication of economic globalization in the social life in China; Cultural tensions manifested between society and the intellectual sphere in China and Japan; Intellectual community dialogue between China and Japan on the issue of cultural differences.

The article focuses on the effort of Chinese government to implement environmental policies particularly on forest hydrology. Forest restoration programs include North shelterbelts projects, natural forest protection program and green for grains program are highly recommended to control soil erosion and flooding and improve water quality management. The government has conducted a research towards the precipitation and potential evapotranspiration (ET) to minimize the water yield in streamflow at the climate variability. Moreover, sustainable afforestation practice is considered for developing forest vegetation.

Some highly pathogenic viruses, such as Chikungunya virus, Japanese encephalitis virus, Yellow fever virus, Dengue virus, Hanta virus, SARS-CoV, and H5N1 avian influenza virus can cause severe infectious diseases. However, the consensus method for detecting these viruses has not been well established. A rapid and sensitive microarray approach for detection of these viruses and a panel of specific probes covering nine genera and 16 virus species were designed. 70-mer oligonucleotides were used at the genus level and 50-mer oligonucleotides were at the species level, respectively. To decrease the interference of the host genome in hybridization, the consensus genus primers were designed and used to reverse transcribe only virus genome. The synthesis of the second strand was carried out with a random primer sequence (5'-GTTTCCCAGTAGGTCTCNNNNNNNN-3'). The amplified products were labeled and processed for microarray analyses. This microarray-based method used the highly conserved consensus primers to synthesize specifically the virus cDNA and could identify effectively Chikungunya virus, Japanese encephalitis virus, Yellow fever virus, Dengue virus, Tick borne encephalitis virus, and H5N1 avian influenza virus. Using this method, one unknown virus isolated from pig brain in Shanxi Province, China was identified. This method may have an important potential application for the diagnosis of virus infection.