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Increasing variability of precipitation induced by climate change raises uncertainties for ecosystem services and agricultural production in the Poyang Lake Basin (PLB), China. Reanalysis precipitation datasets (RPDs) are attractive alternatives for monitoring the hydro‐climate cycles. However, their applicability in China has mainly been evaluated at the national scale, while less attention has been paid to the PLB or southeastern China. Here, we apply various metrics to evaluate the magnitude and spatial similarity of annual, monthly, different intensities and the spatial structure of precipitation from four reanalysis—the fifth global atmospheric analysis dataset of the European Center for Medium‐Range Weather Forecasts (ECMWF) (ERA5), Interim ECMWF Reanalysis (ERA‐Interim), Japanese 55‐year Reanalysis project (JRA55) and Modern‐Era Retrospective analysis for Research and Applications, Version 2 (MERRA‐2), against the rain‐gauges over the PLB during 1980–2018. The results showed that the detection capacity of ERA5 and MERRA2 shifted around 2002, whereas that of ERA‐Interim and JRA55 did not substantially change. Before 2002, ERA‐Interim had the lowest biases for the magnitude of annual, monthly and different intensities of precipitation (except for heavy rain), while ERA5 and MERRA2 had strengths in capturing spatial correlation. Notably, ERA5 and MERRA2 had region‐wide wet and dry biases, respectively, before 2002, which can be attributed mainly to the estimation of flood season precipitation (from April to June) and heavy rain. In contrast, the fractional contribution of light–moderate rain was underestimated and overestimated by ERA5 and MERRA2, respectively. However, after 2002, because of the improved reproducibility of flood season precipitation and heavy rain magnitude, the systematic biases of ERA5 and MERRA2 significantly decreased, especially for ERA5, which outperformed other RPDs on all aspects of precipitation. The conclusions of this paper suggest that the variation of applicability over time should be seriously tested before the utilization of RPDs in hydro‐climate analyses. [ABSTRACT FROM AUTHOR]

A good understanding of spatiotemporal characteristics of historical droughts is important for managing and tackling drought hazards. This paper aims to investigate spatiotemporal variations of drought in mainland China over 1961–2016 based on the standardized precipitation evapotranspiration index (SPEI) at the 1‐ and 12‐month timescales. The trend significance and magnitude of 12‐month SPEI were analysed using the modified Mann–Kendall (MMK) method and Sen's slope values. The empirical orthogonal function (EOF) and ensemble empirical mode decomposition (EEMD) were applied to analyse the spatial patterns and periods in 1‐month SPEI series. The results showed that the temporal fluctuations of SPEI were weaker as the timescale increased. The droughts in 1960s were the severest than in other decades. The sites with SPEI < −5 (denoting the extreme droughts) mainly located in the northwestern and southwestern China. An overall wetter trend was detected in most regions of China, except the belt from northeastern to middle and southwestern China. The 1‐month SPEI had shorter than 1.20‐year of mean periods for the seven sub‐regions and China, while had 0.22–2.95 years of mean periods at different sites. Residuals (decomposed from 1‐month SPEI) showed increasing trends in most of the sub‐regions except sub‐region 3. In northern and northwestern China, longer periods of SPEI were detected. The highest values of EOF1 and EOF2 illustrated the eastern and northeastern China were drought‐sensitive areas. From the correlations between 1‐month SPEI and the atmospheric circulations, the AO was the main physical factor that influenced drought occurrence in mainland China. The identified spatiotemporal characteristics of SPEI could offer references for drought prevention and management in China. [ABSTRACT FROM AUTHOR]

The roles of moisture sources and transport in intraseasonal precipitation variabilities during the preflood season over South China are complex and different. In this paper, ERA‐Interim reanalysis data that were collected four times daily from 1979 to 2017 are used to analyse the variation and influence of moisture transport in intraseasonal precipitation during the preflood season over South China. Using the Hybrid Single‐Particle Lagrangian Integrated Trajectory model, fixed atmospheric moisture sources are defined: land area source (LD source), Indian Ocean source (IO source), Pacific Ocean source (PO source), South China Sea source (SCS source), and South China source (SC source). Sea source moisture transport accounts for more than 75% of the total precipitation during the preflood season, which is the most important moisture source in South China. For April, southeasterly moisture transport, which includes PO source and SCS source moisture transports, is the major moisture transport over South China. Then, the IO source and SCS source precipitation increased significantly during May. During June, the IO source precipitation accounted for 43.75% of the total precipitation, thus dominating precipitation over South China. In addition, there is a significant difference in the interdecadal variation in the preflood season precipitation before and after the Indian summer monsoon onset. Before the Indian summer monsoon onset, the land‐sea thermal contrast decreased, which led to a significant interdecadal reduction in the IO source, PO source, and SCS source moisture transports. After the Indian summer monsoon onset, the increase in IO source moisture transport is the primary cause of the interdecadal increase in precipitation over South China. [ABSTRACT FROM AUTHOR]

Bacteria! abundances in ice cores vary in response to climatic conditions. This paper presents annual bacterial abundances measured in ice deposited over the past 70 years and trapped within a core retrieved from Mount Geladaindong, on the central Tibetan Plateau. The bacterial abundance was lowest in 1938 and highest in 1997. Analyses of correlations between bacterial abundance and δ18O and Ca2+ concentrations indicate that bacterial abundance correlates positively with both temperature and amount of dust transported onto the glacier. These correlations imply that both higher temperatures and more frequent dust deposition influence bacterial abundance in the Geladaindong ice core. Bacterial genetic diversity also changes seasonally, and the diversity during the monsoon season appears much higher than during the nonmonsoon season. Bacterial sequences representing the monsoon season were related to bacteria originating from various environmental conditions while these, representing the nonmonsoon season, were typically related to microorganisms coming from cold environments and soils. [ABSTRACT FROM AUTHOR]

Sensible heat flux greatly influences the Indian monsoon. In this study, we calculated sensible heat flux time-series for 12 sites over the western Tibetan Plateau using Price and Dunne's formula and adjusting the stability function. The time-series were derived from the field observations from the GEWEX Asian Monsoon Experiment (GAME)/Tibet programme under the Global Energy and Water Cycle Experiment (GEWEX). This paper demonstrates that monthly sensible heat fluxes show strong correlations with corresponding precipitation, and that the correlation coefficients increase with precipitation amount. The preceding winter and spring solid precipitation (snowfall and resulting snowpack) can also influence sensible heat flux in May, but the situation is complex. The correlations between heat flux and snowfall at Amdo, Naqu, and Lhasa are negative, but they are positive at Gaize (also known as Gerze) and Dingri. There is a significant relationship between how the variations from the mean calculated heat fluxes at Amdo differ from those at Rikaze, or Dingri, Cuona and Longzi, and their respective June-September precipitation amounts. This phenomenon may result from changes in circulation. When the sensible heat fluxes are above average north of the influence of the Indian monsoon and below average to the south, the summer monsoon circulation develops early and with greater intensity and precipitation, and vice versa. [ABSTRACT FROM AUTHOR]

Global circulation models (GCMs) are routinely used to project future climate conditions worldwide, such as temperature and precipitation. However, inputs with a finer resolution are required to drive impact‐related models at local scales. The non‐homogeneous hidden Markov model (NHMM) is a widely used algorithm for the precipitation statistical downscaling for GCMs. To improve the accuracy of the traditional NHMM in reproducing spatiotemporal precipitation features of specific geographic sites, especially extreme precipitation, we developed a new precipitation downscaling framework. This hierarchical model includes two levels: (1) establishing an ensemble learning model to predict the occurrence probabilities for different levels of daily precipitation aggregated at multiple sites and (2) constructing a NHMM downscaling scheme of daily amount at the scale of a single rain gauge using the outputs of ensemble learning model as predictors. As the results obtained for the case study in the central‐eastern China (CEC), show that our downscaling model is highly efficient and performs better than the NHMM in simulating precipitation variability and extreme precipitation. Finally, our projections indicate that CEC may experience increased precipitation in the future. Compared with ~26 years (1990–2015), the extreme precipitation frequency and amount would significantly increase by 21.9%–48.1% and 12.3%–38.3%, respectively, by the late century (2075–2100) under the Shared Socioeconomic Pathway 585 climate scenario. [ABSTRACT FROM AUTHOR]

Autumn precipitation in the central region of China (APCC) can considerably influence on agricultural production and human livelihood. With reanalysis data from 1979 to 2020, it revealed that APCC is significantly affected by the second mode of the meridional wind field at 200 hPa over the Eurasian continent on the interannual scale, which featured a quasi‐barotropic "+‐+" wave‐like pattern from Europe to China (EC pattern) in extratropical zone. When the EC pattern is in a positive phase, central China lags behind the downstream positive geopotential height (anticyclone) anomaly. In this context, the transport of moisture from the south and east is enhanced and the advancement of the southerly monsoon is blocked, providing sufficient water vapor to support the occurrence of APCC. Further diagnosis revealed that local ascending motion is strengthened owing to the warm advection induced by anomalous southerly and positive vorticity advection associated with the anomalous anticyclone over East Asia. Additionally, wave flux analysis and model simulation suggest that the EC pattern results from the propagation of stationary Rossby wave, which could be excited by dipole sea surface temperature anomalies in the North Atlantic. These discoveries will contribute to improving the predictability of APCC. Plain Language Summary: The interannual variability of autumn precipitation in central China (APCC) is largely affected by a wave train over the Eurasian continent (EC pattern), which can influence the local moisture and dynamic uplift conditions by an anomalous anticyclone over East Asia. The North Atlantic dipole sea surface temperatur anomalies play an important role in the prediction of APCC, and could stimulate an extratropical teleconnection to shape the EC pattern over the Eurasian continent, as confirmed in the linear baroclinic model. Key Points: The autumn rainfall in central China is related to the second mode of V200 (EOF2) over the Eurasian continent on interannual timescaleEOF2 features in a "+‐+" wave‐like pattern, resulting in an anticyclone anomaly over East Asia in its positive phaseExtratropical EOF2 pattern wave train could be excited by the North Atlantic dipole sea surface temperature anomaly [ABSTRACT FROM AUTHOR]

This paper studies the coherent modes of multi-scale variability of precipitation over the headwater catchments in the Pearl River basin in South China. Long-term (1952-2000) daily precipitation data spatially averaged for 16 catchments in the basin are studied. Wavelet transform analysis is performed to capture the fluctuation embedded in the time series at different temporal timescales ranging from 6 days to 8.4 years. The catchment clusters of the coherent modes are delineated using the principal component analysis on the wavelet spectra of precipitation. The results suggest that as much as 98% of the precipitation variability is explained by only two coherent modes: high small-scale mode and high seasonal mode. The results also indicate that a large majority of the catchments (i.e., 15 out of 16) exhibit consistent mode feature on multi-scale variability throughout three sub-periods studied (1952-1968, 1969-1984, and 1985-2000). The underlying effects of the coherent modes on the regional flood and drought tendency are also discussed. [ABSTRACT FROM AUTHOR]

The north China July precipitation (NCJP) accounts for the largest proportion of annual total precipitation in north China and displays a significant decadal variability of a cycle about 20‐year at least from the past 40 years. There is a significant negative correlation between the July northern North Atlantic sea surface temperature (NNASST) and NCJP on decadal scale. When the detrended July NNASST anomaly is in negative phase, the NCJP anomaly is in positive phase, and vice versa. We present the coupled oceanic–atmospheric bridge (COAB) mechanism of the July NNASST influences on NCJP decadal variability via the Eurasian decadal teleconnection (EAT) pattern: the NNASST stimulates the EAT pattern which regulates circulation anomalies in north China and its surrounding regions, and finally regulates precipitation anomalies in north China by influencing the local water vapour transport. In addition, a preliminary analysis about the causes of the super‐abnormal NCJP in 2021 indicates that the super‐abnormal NCJP in 2021 is not just the decadal role of the NNASST on NCJP, may be the combined influence of the WPSH in the northeastern of north China, the abnormal high pressure in the northwest and the low‐pressure cyclone in the south in the rainy decadal background. [ABSTRACT FROM AUTHOR]

Knowledge of the responses and feedbacks of vegetation dynamics to interannual climate anomalies in the semiarid area of north China is lacking. This study addresses this issue through climate modelling for 1991–2006 with the Weather Research and Forecast (WRF) model, into which a locally empirical vegetation dynamic (VED) scheme was implemented. The VED scheme was built on the basis of regression models of the leaf area index (LAI), green vegetation fraction (GVF), and surface albedo (ALB) with ambient temperature and humidity as independent variables. Using the update WRF model, the climate simulations were carried out with turning on and off VED, respectively. By comparing the simulations outputs with each other, we find that the interannual variability of precipitation from simulations with turning on VED is larger than that from simulations with turning off VED. The larger interannual variability of precipitation could be explained by VED feedback. Vegetation growth would be more vigorous, as a response, under the more precipitation, because which brings more available water. In turn, vigorous vegetation leads to more evapotranspiration and, hence, precipitable water; as a result, there would be more precipitation. It is reversed for the years with less precipitation. Such interactions between vegetation and precipitation could be summarized as positive feedback loops. This study suggests that the interannual precipitation variability can be enlarged by VED through positive evapotranspiration–precipitation feedback. It is therefore necessary to consider the vegetation dynamics for future downscaled regional climate predictions to pursue more reliable interannual climate variability. [ABSTRACT FROM AUTHOR]

The effects of aridity on ecosystems and water cycles are pronounced and have received considerable attention. However, aridity changes due to future warming and its regional variability over China remain uncertain. This paper aims to identify the spatiotemporal variations in aridity and its key influencing factors over China in the mid-21st century based on five general circulationmodels (GCMs) and four representative concentration pathway (RCP) scenarios. An aridity index (AI), defined as the ratio of reference evapotranspiration (ETo) to precipitation (P), was calculated. We show that the GCMensemble means are able to reproduce the variation of aridity during the baseline period. Generally, ETo anomalies are consistently positive. Other than for the RCP2.6 low-emission scenario, precipitation and aridity are both projected to increase. There are pronounced regional differences in aridity changes; i.e. wetter across most of western China and drier across most of eastern China in the mid-21st century. Negative AI anomalies in western China can be attributed mainly to the projected increase in precipitation. In eastern China, the AI was higher despite positive precipitation anomalies, due mainly to the greater effect of climate change on increasing atmospheric moisture demand. This suggests that evapotranspiration demand should be incorporated into aridity changes under future warming. [ABSTRACT FROM AUTHOR]

Paleoclimatic records reveal spatially asynchronous changes of East Asian summer monsoon (EASM) precipitation during the Holocene, but the underlying mechanisms are not fully understood. This study explores the role of the zonal shift of the Asian westerly jet (AWJ) core on the spatial‐temporal variability of EASM precipitation based on Holocene climate simulations using the KCM and CESM forced by orbital variations. We analyzed the composite differences of summer precipitation and associated atmospheric circulations between the early (middle) and middle (late) Holocene. Simulations suggest a dipole pattern of summer precipitation with increasing (decreasing) precipitation in central (southern) China from the early to late Holocene, which was shaped by the eastward shift of the AWJ core. The eastward shift of the AWJ core and the accompanied eastward movement of the upper‐level convergence over the AWJ's right exit region weakened the low‐level downward motions over central China. Meanwhile, the low‐level upward motions over southern China were weakened by the concurrent eastward (westward) migration of the South Asian High (western Pacific subtropical High) during the Holocene. Consequently, summer precipitation increased (decreased) in central (southern) China from the early to late Holocene. The eastward shift of the AWJ core was primarily driven by amplified meridional insolation gradient at middle latitudes via strengthening upper‐level westerly intensity during the Holocene. In addition, land cover difference between East Asia and central Asia caused a greater enhancement of westerlies intensity in East Asia, further modulating the eastward movement of the AWJ core during the Holocene. Key Points: Our simulations reveal a dipole pattern of summer precipitation between central and southern China during the HoloceneThe dipole precipitation pattern was strongly modulated by zonal shift of the Asian westerly jet coreInsolation variation and land cover caused the eastward shift of the Asian westerly jet core during the Holocene [ABSTRACT FROM AUTHOR]

This study identifies the variability of large‐scale atmospheric patterns (LSMPs) and atmospheric moisture circulation patterns associated with the variability of daily precipitation over East China using the self‐organizing maps (SOM) method. The spatiotemporal characteristics of the occurrence and intensity of daily precipitation were linked with the variabilities of LSMPs. Results show that the synoptic moisture transport over East China in both dry season and rainy season can be classified into eight patterns, and the occurrence frequency and primary occurring months of the eight patterns are varied. In the dry season, the wetter pattern (the drier pattern) exhibits a significant decreasing (increasing) trend with a slope of −0.23 (0.63)% year−1 at the confidence level of 0.95 during 1979–2018. The LSMPs corresponding to each atmospheric moisture circulation pattern, including the composite mean values of vertically integrated water vapour transport fields, 500 hPa geopotential height (Z500) anomalies and sea surface temperature anomalies (SSTA) in surrounding oceans, indicate that the primary oceanic moisture source of the dry season is western North Pacific (WNP), while that of the rainy season is WNP and the Indian Ocean. The location and intensity variabilities of subtropical high affect the transport and amount of water vapour along with its western flank to arrive in East China. SSTA has an influential link with the regional circulations and convection activity, and thus plays an important role in affecting water vapour transport. [ABSTRACT FROM AUTHOR]

This study investigates the interannual variability of winter precipitation over the Three River Source (TRS) region in China based on precipitation observations collected at stations in the TRS region and reanalysis datasets for the period of 1980–2015. The results suggest that the TRS winter precipitation has distinct interannual variability with discordant trends in different months, that is, an increasing trend is found in November and February, a decreasing trend is found in other winter months, and interannual variations in precipitation are different in different months. The mechanisms for the interannual variation in monthly precipitation over the TRS region are significantly different in different winter months. The interannual variability of TRS precipitation in November is modulated by an anomalous westerly water vapour transport (WVT) branch. This anomalous WVT branch is related to a North Atlantic‐Europe‐Tibetan Plateau (NA‐E‐TP) wave‐train that originates in the North Atlantic due to the ocean–atmosphere interaction. In December, a circum‐global teleconnection (CGT) wave‐train can induce anomalous westerly WVT in the TRS region, resulting in increased precipitation there. This CGT wave‐train is triggered by warm SST anomalies in the central‐eastern tropical Pacific associated with the El Niño‐Southern Oscillation (ENSO). The interannual variability of TRS precipitation in January and February is affected by southwesterly WVT anomalies over the TRS region, which are associated with a southeastward propagating wave‐train over Eurasia caused by the North Atlantic Oscillation (NAO). In March, the interannual variability of TRS precipitation is modulated by the leading mode of the Eurasian circulation that resembles the Scandinavian (EU1) pattern, which can cause anomalous southwesterly WVT in the TRS region. In winter, the characteristics of sea surface temperature anomalies, weather systems, and atmospheric circulations associated with interannual variations of monthly precipitation in the TRS region are different for individual winter months. [ABSTRACT FROM AUTHOR]

In this study, simulations of 13 all‐forcing experiments from the Community Earth System Model Last Millennium Ensemble (CESM‐LME) archive were used to investigate the different spatiotemporal characteristics and corresponding mechanisms of the decadal megadroughts over the eastern China during two typical periods in the past millennium, that is, Medieval Climate Anomaly (MCA) and Little Ice Age (LIA). The results show that there is no significant difference in either megadrought intensity or duration between the MCA and LIA, but there are significant differences in the megadrought frequencies. The frequency of megadroughts during the MCA is 1.44 times/hundred years, compared with 1.69 times/hundred years in LIA. Results from solar only sensitivity experiments and volcanic only sensitivity experiments show that this difference is mainly induced by the solar radiation. The mechanism analyses show that a spatial pattern of sea surface temperature anomalies (SSTA) resembling the positive Pacific Decadal Oscillation (PDO)‐like pattern have occurred simultaneously with the megadroughts during both the MCA and LIA. While, the megadroughts in MCA are strongly correlated with the strong PDO‐like SSTA patterns, and the megadroughts in LIA are strongly correlated with the weak PDO‐like SSTA patterns. In addition, the anomalous sea level pressure (SLP) field and wind field associate with the megadroughts during the MCA and LIA are consistent with the strengths of SSTA, with significant larger SLP and wind anomalies during the MCA than those during the LIA. Therefore, it can be concluded that the responses of the large‐scale atmospheric circulation patterns to SSTA are similar during these two typical periods, and the difference in the megadrought frequencies is due to the nonlinear response of the precipitation variability to the large‐scale atmospheric circulation patterns. [ABSTRACT FROM AUTHOR]

Precipitation is a crucial element in the study of climate change and is a key component of climate change processes and the hydrological cycle. Changes in precipitation therefore have wide ranging implications across various fields, including agriculture, ecology and economic development. Known as the 'Mother River of China', the Yellow River is the sixth longest river in the world and the second‐longest in the country, and has a unique political, economic and cultural role in China. Flowing through arid, semi‐arid and semi‐humid regions, it is well known for its high sand content and limited water resources. Precipitation in the Yellow River Basin (YRB) directly affects not only water security, but also eco‐system health and socio‐economic development. As a climatic phenomenon with characteristics that vary across both space and time, precipitation pattern analysis requires the examination of spatiotemporal changes. This study made use of interpolation grids in the analysis of data from all rainfall gauges associated with the National Meteorological Information Center and China Meteorological Administration; this constitutes a new and more representative method of assessing the spatiotemporal distribution of precipitation over the entire Yellow River basin. Moreover, the precipitation records for the last decade – in which significant variation has been found – were reanalysed to assess changes in precipitation patterns over the region. The results showed a slight increase in precipitation in the upper reaches of the river and the northern part of the basin, along with a slight decrease in the southern part and a significant increasing trend from 1990 to 2009 for areal average annual precipitation. The locations of annual precipitation maxima shifted to the west, especially for the 400mm isoline. Relative to the 1956–2000 series, the new updated series showed a reverse movement for the 400mm precipitation contours. The Hurst exponent indicated the presence of a random series for the longitudinal movement data and a sustained state for the latitude data. The potential drivers of variation in precipitation over the YRB were also explored, and an increase in the extent of vegetation cover was identified as the dominant influencing factor. However, given the huge uncertainty in projections of future global warming, climate change impacts should also be considered; for example, rapid temperature increases might result in the degradation of vegetation cover. The results of the study indicate that there is the potential for an increased risk of both urban and rural flooding in the YRB, with its unique water–sediment conditions, along with negative outcomes for agriculture and the eco‐environment. [ABSTRACT FROM AUTHOR]

The Xilingol steppe, located in Inner Mongolia, northern China, is a natural grassland well known for producing high-quality feed for grazing animals. Our regression analysis using the meteorological data recorded at the Xilingol Meteorological Observatory from 1953 to 2000 (48 years) indicated that the annual mean temperature rose by 2.66°C during 50 years from 1953, while the mean temperature during the plant growing season (April-October) rose by 2.10°C during the same period. These temperature rises at the Xilinhot Observatory are more than twice that found in other regions of China. In the same 48-year period, no significant changes in annual precipitation amounts were noted; however, the annual precipitation days significantly decreased. We must clarify the factors causing climate change in this region and how such change will impact future productivity and biodiversity in this semiarid grassland. [ABSTRACT FROM AUTHOR]

This study aims to determine temporal trends and spatial distribution of the annual and monthly precipitation in the Haihe River Basin, China, during 1951-2008. A significant decreasing trend was observed for the annual precipitation, mainly attributed to the abrupt decrease in the flood-season precipitation (June-September) around the year of 1979. No significant trend was revealed for precipitation within Period I of 1951-1979 and Period II of 1980-2008. Results of this study indicated that the relative contributions of the flood-season precipitation decreased temporally with time and spatially with elevation. This study also identified a potential movement of storm centers from east to west portions of the basin. In addition, analysis on the precipitation anomalies also suggested a redistribution of the non-flood season precipitation over the study area. Compared with the west portion of the basin, generally, the east received relatively more precipitation during the non-flood season, while similar trend of precipitation redistribution was not observed in the flood season. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study, soil respiration and environmental variables were examined to explore the temporal and spatial variability and controls of soil respiration in eight plant communities along an east-west transect in a temperate steppe of Inner Mongolia, China. Our results show that there was substantial temporal (coefficient of variation (CV)= 58.6 ± 1.54%, n = 14) and spatial variability (CV = 32.6 ± 2.65%, n = 8) in soil respiration. Soil temperature and moisture were more important than plant growth in controlling the seasonal patterns of within-site soil respiration in all the eight steppe communities. Spatial differences in soil respiration rate could be mainly attributed to the differences in soil moisture and net primary productivity (NPP) among the study sites, whereas soil temperature played a minor role in regulating the spatial pattern of soil respiration. Significantly, positive site-to-site correlations were found between soil respiration and site soil traits such as soil C, N, and clay contents. in contrast, soil respiration was negatively correlated with soil bulk density and sand content. These findings indicate that the relative importance of abiotic and biotic factors in regulating soil respiration differs temporally from spatially. The conclusions drawn from the present study provide valuable information for developing future models of soil respiration driven by site climatic and soil variables, applicable for large-scale estimates of soil respiration in grassland ecosystems. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the temporal trends and spatial distribution of precipitation, air temperature, evapotranspiration and runoff in the Yiluo River basin in China. It notes the use of Mann-Kendall, Yamamoto and linear fitted models in exploring the climatic variability. It discusses the implication of the findings on the temporal trends of the variables, the downward trend of annual runoff and the vegetation changes.

The article discusses the impacts of climate variability on the regional stream-flow in the Yellow River in China. The research results conclude that the average annual precipitation is 494-8 millimeters during the years of the La Niña storm are greater than that in the years of El Niño storm years. The authors explain that both precipitation and stream-flow responses show temporal and spatial patterns. The connection between the stream-flow, precipitation, and temperature indicates that stream-flow is sensitive to both precipitation and temperature.