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Used to reduce damage from rainfall-induced landslides and establish disaster-warning systems, physically based stability models are efficient tools for evaluating spatial or temporal patterns of susceptibility to shallow landslides. Such comprehensive models can be classified as dynamic and steady hydrological models, which combine the simulation of dynamic or steady-state subsurface saturation generation with slope stability analysis. Although numerous dynamic and steady models have been proposed and validated against actual landslides, comprehensive comparisons of the performance and detection preferences for topographic characteristics (hereafter, topographic preferences) between the dynamic and steady models are lacking. Based on detailed observational data on topography at the soil–bedrock interface, this study compared numerical predictions from dynamic and steady models to a case of rainfall-induced shallow landslides in a small catchment. The dynamic model was based on time-varying generation of subsurface saturation using the three-dimensional Richards equation, and the steady model was based on the steady-state distribution of subsurface saturation. The results showed that both the dynamic and steady models could generally detect cells at risk of failure in the landslide areas. However, the precision of the dynamic model was approximately double that of the steady model. Rainfall patterns had significant impacts on the timing and locations of landslides, and the delayed rainfall peak pattern was most prone to landslides, which was reflected by the dynamic model but not the steady model. The steady model underestimated instability or the number of unstable locations relative to the dynamic model. This study revealed that the topographic preference at the soil–bedrock interface differs between the models. The dynamic model exhibited topographic preference in detecting landslides with deep soil depth and steep gradient, whereas the steady model was better for detecting landslides with large contribution areas. The elucidation of such topographic preferences for landslide types is crucial for comparing the performance of dynamic and steady models.

Context The COVID-19 pandemic has been affecting health and economies across the world, although the nature of direct and indirect effects on Asian agrifood systems and food security has not yet been well understood. Objectives This paper assesses the initial responses of major farming and food systems to COVID-19 in 25 Asian countries, and considers the implications for resilience, food and nutrition security and recovery policies by the governments. Methods A conceptual systems model was specified including key pathways linking the direct and indirect effects of COVID-19 to the resilience and performance of the four principal Asian farming and food systems, viz, lowland rice based; irrigated wheat based; hill mixed; and dryland mixed systems. Based on this framework, a systematic survey of 2504 key informants (4% policy makers, 6% researchers or University staff, 6% extension workers, 65% farmers, and 19% others) in 20 Asian countries was conducted and the results assessed and analysed. Results and conclusion The principal Asian farming and food systems were moderately resilient to COVID-19, reinforced by government policies in many countries that prioritized food availability and affordability. Rural livelihoods and food security were affected primarily because of disruptions to local labour markets (especially for off-farm work), farm produce markets (notably for perishable foods) and input supply chains (i.e., seeds and fertilisers). The overall effects on system performance were most severe in the irrigated wheat based system and least severe in the hill mixed system, associated in the latter case with greater resilience and diversification and less dependence on external inputs and long market chains. Farming and food systems' resilience and sustainability are critical considerations for recovery policies and programmes, especially in relation to economic performance that initially recovered more slowly than productivity, natural resources status and social capital. Overall, the resilience of Asian farming and food systems was strong because of inherent systems characteristics reinforced by public policies that prioritized staple food production and distribution as well as complementary welfare programmes. With the substantial risks to plant- and animal-sourced food supplies from future zoonoses and the institutional vulnerabilities revealed by COVID-19, efforts to improve resilience should be central to recovery programmes. Significance This study was the first Asia-wide systems assessment of the effects of COVID-19 on agriculture and food systems, differentiating the effects of the pandemic across the four principal regional farming and food systems in the region.

The lack of rapid and efficient diagnostics impedes largely the epidemic control of multidrug-resistant tuberculosis, and might misguide the therapeutic strategies as well. This study aimed to identify novel multidrug-resistant tuberculosis biomarkers to improve the early intervention, symptomatic treatment and control of the prevalence of multidrug-resistant tuberculosis. The serum small molecule metabolites in healthy controls, patients with drug-susceptible tuberculosis, and patients with multidrug-resistant tuberculosis were screened using ultra-high-performance liquid chromatography combined with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The differentially abundant metabolites were filtered out through multidimensional statistical analysis and bioinformatics analysis. Compared with drug-susceptible tuberculosis patients and healthy controls, the levels of 13 metabolites in multidrug-resistant tuberculosis patients altered. Among them, the most significant changes were found in N1-Methyl-2-pyridone-5-carboxamide (N1M2P5C), 1-Myristoyl-sn-glycerol-3-phosphocholine (MG3P), Caprylic acid (CA), and D-Xylulose (DX). And a multidrug-resistant tuberculosis/drug-susceptible tuberculosis differential diagnostic model was built based on these four metabolites, achieved the accuracy, sensitivity, and specificity of 0.928, 86.7%, and 86.7%, respectively. The enrichment analysis of metabolic pathways showed that the phospholipid remodeling of cell membranes was active in multidrug-resistant tuberculosis patients. In addition, in patients with tuberculosis, the metabolites of dipalmitoyl phosphatidylcholine (DPPC), a major component of pulmonary surfactant, were down-regulated. N1M2P5C, MG3P, CA, and DX may have the potential to serve as novel multidrug-resistant tuberculosis biomarkers. This research provides a preliminary experimental basis to further investigate potential multidrug-resistant tuberculosis biomarkers. IMPACT STATEMENT: The MDR-TB incidence remains high, making the effective control of TB epidemic yet challenging. Rapid and accurate diagnosis is vitally important for improving the therapeutic efficacy and controlling the prevalence of drug resistance TB. Metabolomics has dramatic potential to distinguish MDR-TB and DS-TB. N1M2P5C, MG3P, CA, and DX that we identified in this study might have potential as novel MDR-TB biomarkers. The phospholipid remodeling of cell membranes was highly active in MDR-TB. The DPPC metabolites in TB were significantly down-regulated. This work aimed to investigate potential MDR-TB biomarkers to enhance the clinical diagnostic efficacy. The metabolic pathway distinctly altered in MDR-TB might provide novel targets to develop new anti-TB drugs.

Stemflow contributes to an uneven water input and preferential infiltration and percolation that increases the heterogeneity of soil water dynamics in forested stands. These aboveground and underground effects are referred to as the double-funneling effect of a tree. Stemflow serves as a principal source of the rainwater input around a tree, and tends to enter the soil over a small infiltration area and then preferentially flow along the network of root channels. This kind of concentrated infiltration and channelization of stemflow could generate perched water in soil layers or at the soil–bedrock interface. The double-funneling effect also influences the soil water redistribution process and the spatial pattern of soil water during the drying process. The double-funneling effect has been qualitatively demonstrated for various species with links to soil erosion, subsurface flow, slope stability, groundwater recharge, and runoff generation at various scales. A comprehensive and integrated understanding of the double-funneling effect is needed. This chapter reviews the current understanding of how stemflow affects soil water dynamics in both wetting and drying processes. After discussing field evidence of the effects of stemflow on soil water responses, their modeling and issues requiring future study are highlighted.

Surface soil moisture has been extensively studied for various land uses and landforms. Although many studies have reported potential factors that control surface soil moisture over space or time, the findings have not always been consistent, indicating a need for identification of the main factors. This study focused on the static controls of topographic, soil, and vegetation features on surface soil moisture in a steep natural forested headwater catchment consisting of three hillslope units of a gully area, side slope, and valley-head slope. Using a simple correlation analysis to investigate the effects of the static factors on surface soil moisture at 0–20 cm depths at 470 points in 13 surveys, we addressed the characteristics of surface soil moisture and its main controlling factors. The results indicated that the mean of surface soil moisture was in the decreasing order of gully area > valley-head > side slope. The relationship between the mean and standard deviation of surface soil moisture showed a convex-upward shape in the headwater catchment, a negative curvilinear shape in the gully area, and positive curvilinear shapes at the side and valley-head slopes. At the headwater catchment and valley-head slope, positive contributions of soil porosity and negative contributions of slope gradient and saturated hydraulic conductivity were the main controlling factors of surface soil moisture under wetter conditions, whereas positive contributions of topographic wetness index and negative contributions of vegetation density were the main controlling factors of surface soil moisture under drier conditions. At the side slope underlain by fractured bedrocks, only saturated hydraulic conductivity and vegetation density were observed to be controlling factors. Surface soil moisture in the gully area was mainly affected by runoff rather than static features. Thus, using hillslope units is effective for approximately estimating the hydrological behaviors of surface moisture on a larger scale, whereas dependency between the main static factors and moisture conditions is helpful for estimating the spatial distributions of surface moisture on a smaller scale.

Subsurface saturation near the bedrock surface is an important source of runoff generation and deeper bedrock recharge. While many studies have reported the generation patterns of subsurface saturation on valley side slopes or unchanneled catchments, studies focusing on the relationship between bedrock topography and subsurface saturation dynamics in a headwater catchment are still rare. This study therefore analyzed the effects of bedrock topographic features on subsurface saturation generation based on a dataset of pore water pressure (ψ) observations at the soil–bedrock interface and the spatial distributions of soil depth and the topographic wetness index (TWI) of bedrock topography in a steep natural forested headwater catchment. Temporal variations in the mean and standard deviation of ψ were lower at the perennially saturated points but higher at the ephemerally saturated points. The expansion patterns of subsurface saturation during storm events could be classified into four stages: fragmentary and unconnected distributions, both downward and upward expansions, interconnection from upslope to downslope, and disappearance from the middle slope. When saturation was interconnected, 41% of accumulated rainfall contributed to increases of subsurface saturation with a highly linear relationship. Soil depth correlated negatively with the increase in ψ at all points and at ephemerally saturated points. These negative correlations occurred frequently after the generation of new saturation, and remained for a short period around the early peaks of rainfall when the mean of ψ increased sharply. TWI correlated positively with ψ and ψ ⩾ 0 among all points but not in the subsets of perennially or ephemerally saturated points. The positive correlations became more significant after generation of new saturation. Overall, this study demonstrates that the effects of soil depth and TWI on subsurface saturation vary with space and time in a steep natural forested headwater catchment. These effects are combined in a short time when new saturation is generated.

Subsurface displacement can be a sign of shallow or deep-seated landslides. Although forested headwaters feature primarily active hydrological responses and erosional responses, the impacts of invisible subsurface displacement on hydrological responses are rarely reported. This study presents the changes in hydrological responses before and after subsurface displacement in a natural forested headwater. Using event-based analyses, the maximum values of rainfall, pore water pressure at the soil–bedrock interface, and surface runoff during rainfall events over 2 years were used to evaluate the changes in peak responses after subsurface displacement. The results showed that subsurface displacement increased the maximum pore water pressure, but reduced the rate of increase in pore water pressure, particularly for the measurement points where perennial subsurface saturation existed. Peak runoff was produced with at least two sources of near-surface flow and subsurface flow. Subsurface displacement reduced both the level and rate of increase in peak runoff. The internal relations in pore water pressure and the correlations between pore water pressure and runoff weakened after displacement. This weakening was likely due to displacement-induced cracks facilitating rainwater percolation into bedrock layers, and thereby decreasing the linkage between subsurface saturation and surface runoff. Subsurface displacement also modified the response time such that the maximum responses in pore water pressure and runoff tended to occur earlier than maximum rainfall during the period after displacement. This study demonstrates that invisible subsurface displacement directly changes hydrological behaviors, and that a headwater area is active, sensitive, and prone to disturbance, even if it is covered by forest.

To identify a strategy for earlier sowing and harvesting of spring maize ( Zea mays L.) in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of China Agricultural University in 2014 and 2015. A short-season cultivar, Demeiya number 1 (KX7349), was used in the experiment. Soil temperature to 5 cm depth in the early crop growth stage, crop growth, crop yield, and water use of different treatments (plastic film-mulched raised bed (RF) and flat field without plastic film mulching (CK) in 2014; RF, plastic film-mulched flat field (FF), and CK in 2015) were measured or calculated and compared. Soil temperature in the film-mulched treatments was consistently higher than that in CK (1.6–3.5 °C in average) during the early growth stage. Crops in plastic film-mulched treatments used 214 fewer growing-degree days (GDDs) in 2014 and 262 fewer GDDs in 2015. In 2014, the RF treatment yielded 32.7% higher biomass than CK, although its 9.4% higher grain yield was not statistically significant. Also, RF used 17.9% less water and showed 33.1% higher water use efficiency (WUE) than CK. In 2015, RF and FF showed 56.2% and 49.5% higher yield, 15.0% and 4.5% lower water use (ET), and 63.4% and 75.7% higher WUE, respectively, than CK. RF markedly increased soil temperature in the early crop season, accelerated crop growth, reduced ET, and greatly increased crop yield and WUE. Compared with FF, RF had no obvious effect on crop growth rate, although soil temperature during the period between sowing and stem elongation was slightly increased. However, RF resulted in lower ET and higher WUE than FF. Effects of RF on soil water dynamics as well as its cost-effectiveness remain topics for further study.

The generation of subsurface saturation is highly related to shallow landslide initiation. Although many studies have relied on experiments to report the generation processes of subsurface saturation that triggers shallow artificial landslides, studies based on detailed in situ monitoring data sets or pre- and post-slide data sets for a natural landslide are still rare. This study recorded the dynamics of pore water pressure at the soil–bedrock interface with high spatiotemporal resolution concurrently with the occurrence of a shallow landslide in a steep natural forested headwater catchment. Using event-based analyses, we explored patterns in the generation of subsurface saturation and other main hydrological factors triggering the landslide. The landslide was not induced by the event with the greatest rainfall amount but by a smaller event with intermittent rainfall over a long duration of 9 days and intense rainfall from the seventh day. The landslide occurred as a result of record-high subsurface saturation generation with a spatial mean pore water pressure of 17.5 cmH2O and a saturation ratio of 0.89 at the site. It was attributed to the landslide event that began during wet conditions with a mean pore water pressure of 7.2 cmH2O. Although the rainfall contributed a near-uniform increase in pore water pressure at all measurement points, high pore water pressure was recorded within the landslide area in the downslope area of the site where subsurface saturation existed perennially. Heterogeneous distribution of subsurface saturation, including perennial and ephemeral saturation, was likely related to the extent of the landslide area. In addition, the two biggest events in the observation period caused subsurface displacements in the year before the landslide. The subsurface displacements weakened the geological structure and enlarged the amount of perennial saturation, which all reduced slope stability and facilitated the landslide. At least two origins of subsurface saturation should be a general feature for a headwater catchment (e.g., vertically downward infiltrated water and an upward rise in groundwater), and the different generation processes of subsurface saturation should be considered separately in future stability analysis models or disaster warning systems for shallow landslides.

Biomass yields and concentrations of crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude fiber (CF) were analyzed for five cultivars of summer-sown maize (Zea mays L.) stover grown in field trials at three rates of N fertilization, and sampled immediately after grain harvest. The results revealed differences in yields and concentrations of nutrients according to stalk height and hence harvest portion among the cultivars. N application greatly increased biomass yield and CP, especially in upper stalks and to a lesser extent, EE. Concentrations of NDF and ADF decreased as N rate increased. The results show that stovers from all local popular maize cultivars are suitable as animal fodder and that moderate N application improves feed quality of stover.

Although many studies have investigated the ecological or hydrological influences of stemflow on soil water dynamics in the wetting process, the process by which stemflow affects soil water redistribution in the drying process has rarely been discussed. To address how soil water depletion occurs around a tree and the effects of stemflow on soil water depletion, we used a 2-year data set of soil water content to compare soil water depletion in the drying process before (SF period) and after (no-SF period) the interception of stemflow around a tree on a hillslope. The results revealed a dramatic soil water depletion at locations in the downslope area near to the tree, which was attributed to stemflow and root-induced pathways. The effect of stemflow on soil water depletion was significant in the short period (0.5 h) after the end of rainfall events, which increased the initial soil water content at the start of drying. The effect of root-induced pathways enhanced drainage during the drying process and resulted in irregular vertical distributions of changes in soil water content. Although soil water depletion at locations near to a tree would be expected to be greater than in locations farther away, due to root uptake in the drying process, most soil water depletion in the vicinity of a tree occurred in the SF period rather than the no-SF period. This was mainly attributed to greater instantaneous soil water depletion due to rainwater drainage rather than evapotranspiration, which occurred in the short period between rainfall events. This study furthers our understanding of the separate involvement of stemflow and root channels in the drying process in a warm temperate climate. We also suggest that the double-funnelling effect of a tree is valid not only for the wetting process but also for the drying process and can result in dramatic variations in soil water dynamics within the stemflow-influenced and root-influenced areas of a forested stand. Copyright © 2014 John Wiley & Sons, Ltd.

Summary The surface or near-surface soil moisture at the interface between atmospheric and terrestrial environments has significant implications for the complex interactions between hydrological processes and ecosystems. Although a number of previous studies have reported the spatial patterns and structures of surface moisture in pasture environments based on large sample sizes, information regarding the detailed spatial patterns and structure of surface moisture in a natural forest environment is still sparse, particularly for steep headwater catchments due to the labor intensity involved and the difficulty of making field measurements. In this study, we measured the detailed surface soil water content at depths of 0–12 cm and 0–20 cm at 470 measurement points using the TDR (time domain reflectometry) method. Thirteen surveys were conducted within 1 year in a steep natural forested headwater catchment with a subtropical monsoon climate in Taiwan. The sample and model variograms were used to evaluate the spatial structure of the surface soil moisture. We also compared the spatial structures of surface moisture in this study with those in a similar study conducted in a flat pasture catchment ( Western et al., 1998 ). For the results at our site, exponential model variograms with the nugget effect well fitted sample variograms, indicating an obvious regional dependence of surface moisture and stationary spatial structures in all surveys. The geostatistical structural characteristics of the nugget varied between 22.70 and 47.40 (% V/V) 2 ; the sill varied between 54.99 and 98.51 (% V/V) 2 ; and the range varied between 10.20 and 58.65 m. The nugget, sill, and range all increased with an increase in soil moisture. The notable anisotropy under dry conditions was attributed to the year-round surface runoff pathway. The sample variograms that represented the spatial structure of soil moisture and reliably estimated the nugget, sill, and range required a sample size of at least 235 at our 0.15-ha site (i.e., a measurement resolution of at least 6.4 m 2 per sample). The pattern of soil moisture was relatively stationary in two gullies and on the side of a hillslope, but it varied on the valley-head hillslope depending on whether conditions were dry or wet. In contrast to previous results for a flat pasture catchment ( Western et al., 1998 ), our results produced a right-skewed histogram of soil moisture under dry or moderately wet conditions, variograms that tended to increase with an increase in soil moisture, anisotropy of soil moisture structure under dry, but not wet, conditions, a need for a 55 times higher measurement resolution associated with the large sample size, and a larger nugget effect in the steep natural forested headwater catchment. This study identified the spatial structure and patterns of surface soil moisture as the primary step in understanding hydrologic processes in a natural forested headwater catchment.

Summary The generation of subsurface saturation has large implications for hydrological response in a catchment. Although rainfall–runoff responses have been observed worldwide in many catchments, the spatiotemporal patterns of soil–water movement and subsurface saturation processes in hillslopes and catchments are not yet fully understood because of the small number of observations and their limited areal extent. Numerical simulation allows for exploration of the entire subsurface saturation process in a hillslope or basin. In this study, as a virtual experiment we used a three-dimensional Richards’ equation and detailed observational data of topography and soil depth to examine the dynamics of subsurface saturated-zone generation in steep hillslopes in a catchment during a storm event. Such a simulation approach had not been previously applied for a catchment-scale area. In order to identify the effects of topographic factors on saturation development, we excluded the influence of the heterogeneity of hydraulic properties and used three generalized hydraulic parameter sets that were previously proposed for environments similar to our site. The resulting waveforms of discharges in the three simulations were quite different and unexpected, which was predominately attributed to the combination of soil and bedrock hydraulic conductivity characteristics. However, common appearances in spatial and temporal variations in the generations of saturated zones were found in the three simulations. Subsurface saturation predominately developed at the soil–bedrock interface where saturated zones were generated fragmentarily and locally at first and then connected to flow downslope, flowing from the upper or middle slope areas to the lower slope area. The fragmentary development of saturated zones in the early stage during the storm event was controlled by soil depth; subsequently, the lateral transfer of saturation was controlled by the topographic wetness index at the soil–bedrock interface, showing an “upper–lower” and “fragment–integration” process. We suggest that it is preferable to define the variable source area by soil depth and the topographic wetness index at the soil–bedrock interface than by the distance to the valley bottom, as in the traditional variable source area concept.

Facing the challenges of an increasing world population, a changing climate and ever depleting resources, agricultural is one of the few options for meeting the demand of food security. It is necessary to apply a dynamic and systematic approach to effectively manage the complex agri-eco production and green processing systems. Indeed, farming systems approach for appropriate technology development and simulation modeling is a result of adopting the system thinking by the agricultural research community...

Global food security requires eco-efficient agriculture to produce the required food and fiber products concomitant with ecologically efficient use of resources. This eco-efficiency concept is used to diagnose the state of agricultural production in China (irrigated wheat–maize double-cropping systems), Zimbabwe (rainfed maize systems), and Australia (rainfed wheat systems). More than 3,000 surveyed crop yields in these three countries were compared against simulated grain yields at farmer-specified levels of nitrogen (N) input. Many Australian commercial wheat farmers are both close to existing production frontiers and gain little prospective return from increasing their N input. Significant losses of N from their systems, either as nitrous oxide emissions or as nitrate leached from the soil profile, are infrequent and at low intensities relative to their level of grain production. These Australian farmers operate close to eco-efficient frontiers in regard to N, and so innovations in technologies and practices are essential to increasing their production without added economic or environmental risks. In contrast, many Chinese farmers can reduce N input without sacrificing production through more efficient use of their fertilizer input. In fact, there are real prospects for the double-cropping systems on the North China Plain to achieve both production increases and reduced environmental risks. Zimbabwean farmers have the opportunity for significant production increases by both improving their technical efficiency and increasing their level of input; however, doing so will require improved management expertise and greater access to institutional support for addressing the higher risks. This paper shows that pathways for achieving improved eco-efficiency will differ among diverse cropping systems.

Sample data for TB PYD, HFYD, and DQY patients and healthy controls. (DOCX 15Â kb)

Although changes in rainfall characteristics have been noted across the world, few studies have reported those in mountainous areas. This study was undertaken to clarify spatial and temporal variations in rainfall characteristics such as annual rainfall amount (Pr), mean daily rainfall intensity (η), and ratio of rain days (λ) in mountainous and lowland areas in Taiwan. To this aim, we examined spatial and year-to-year variations and marginal long-term trends in Pr, η, and λ, based on rainfall data from 120 stations during the period 1978–2008. The period mean rainfall (Pr—) at the lowland stations had strong relationships with the period mean daily rainfall intensity (η¯) and the period mean ratio of rain days (λ¯) during those 31 years. Meanwhile, Pr— was only strongly related to η¯ at mountainous stations, indicating that influences on spatial variations in Pr— were different between lowland and mountainous stations. Year-to-year variations in Pr at each station were primarily determined from the variation in η at most stations for both lowland and mountainous stations. Long-term trend analysis showed that Pr and η increased significantly at 10% and 31% of the total 120 stations, respectively, and λ decreased significantly at 6% of the total. The increases in Pr were mostly accompanied by increases in η. Although stations with significant η increases were slightly biased toward the western lowland area, increases or decreases in Pr and λ were not common. These results contribute to understanding the impacts of possible climate changes on terrestrial hydrological cycles. Copyright © 2012 John Wiley & Sons, Ltd.

Wheat–maize double cropping is the most important cropping system on the Hebei Plain and is one of the most important cropping systems in China. In a scenario of greater food demand, and increasing water and rural labour scarcity, it is critical that the annual productivity of the system is improved in water-energy-cost efficient and low carbon ways. Based on farm surveys, this paper benchmarked the performance of wheat–maize double crops on the Hebei Plain during the 2004–2005 season. These farm yields were assessed both against experimental yields collected from on-farm maximum yield trials conducted during the same 2004–2005 season and relative to simulated estimates of the climate-driven potential productivity of the region. The survey of 362 farms in six counties of the Hebei Plain during the 2004–2005 season found wheat yields ranging from 3375 kg ha −1 to 9000 kg ha −1 with an overall average yield of 6556 kg ha −1 . Maize yields averaged 7549 kg ha −1 and ranged from 3375 kg ha −1 to 11,250 kg ha −1 . The aggregate production for the wheat–maize double crops grown in the 2004–2005 season averaged 14,105 kg ha −1 across the six counties. This was 72% of the average production (19,586 kg ha −1 ) recorded from on-farm trials conducted in each of the six counties and 60% of the simulated average production potential (24,147 kg ha −1 ) for the Hebei Plain in the 2004–2005 season. Thus, the annual productivity of the current cropping system could be increased with currently available technologies by 28%, while a yield increase of 42% is possible if farm yields approach the simulated yield potential. Based on farmer interviews and field observations, a number of real and perceived reasons for the current yield gaps in farmers’ fields were recognised. For instance, irrigation at stem-elongation of wheat is a current recommendation, yet only a proportion of the surveyed farmers were able to follow this strategy due to lack of access to shared irrigation facilities. Improving the region's infrastructure to enable more timely irrigation of crops will be a necessary prerequisite to improved productivity. The results from the farm surveys and on-farm trials indicate that, with current recommended practices, farmers can improve their annual farm productivity and close the current yield gaps. However, the survey identified that increasing system performance and efficiency will require a focus on both agronomic and socio-economic issues.

Summary The characteristics of stemflow were observed in a tall stewartia ( Stewartia monadelpha ) deciduous forest on a hillslope in central Japan, revealing new findings for a previously unreported type of deciduous forest. Using 2-year observations of 250 rainfall events, we analyzed seasonal and spatial variations in stemflow for several trees, and applied additional data sets of throughfall and plant area index (PAI) to produce a rough estimate of seasonal variations in rainfall redistribution processes and canopy architecture for a single tree. Compared to previous findings for other deciduous tree species, the ratios of throughfall, stemflow, and interception to open-area rainfall obviously varied with PAI changes for tall stewartia. Meteorological conditions of rainfall amount, rainfall intensity, wind speed, and wind direction had little effect on stemflow generation, which was mainly affected by variation in canopy architecture. Three novel characteristics of stemflow were identified for several tall stewartia trees. First, the yearly stemflow ratio at the forest-stand level for tall stewartia (12%) was high compared to previous findings on beech and oak stands, indicating tall stewartia has considerably high potential to generate a great amount of stemflow. Second, stemflow tended to be 1.3–2.0 times greater in the leafed period than in the leafless period. Third, the amount of stemflow was 12–132 times greater on the downslope side of the stem than on the upslope side. It likely caused by the uneven area between the upslope and downslope sides of the canopy and by asymmetrical stemflow pathways between the upslope and downslope sides of the trunk due to downslope tilting of the tree trunk.

The test on the model with data collected from two years’ field experiments revealed an ability to satisfactorily simulate crop parameters such as LAI, biomass accumulation and partitioning, yield, and variables influencing crop growth and development as nitrogen uptake by crops and partitioning in different organs, and dynamics of soil water and nitrogen including infiltration and leaching. With the model, crop yield, water use efficiency (WUE), nitrogen use efficiency (NYE) and water-nitrogen leaching at specific soil layers under various water and nitrogen management practices were simulated to provide data used as references for designing sustainable nitrogen and water management practices. The outputs of the simulated experiment with various treatments of irrigation and nitrogen application indicated that crop yield was closely related to water and nitrogen application, crop water use was positively related to irrigation amount, and nitrogen fertilization could improve the crop water use and WUE within certain limits. This is a valuable evidence to be considered in water-saving farming. Nitrogen uptake had a positive relation to nitrogen application, while irrigation to some extent improved its uptake by crops and hence increased NYE. Additionally, irrigation and fertilization had great effects on nitrogen leaching. Thus, in order to improve WUE and NYE, the model showed how nitrogen application and irrigation should be well coordinated.

In forested stands, precipitation is intercepted by the canopy and partitioned into throughfall and stemflow as diffuse input and point input, respectively. Therefore, the water reaching the forest floor is not spatially uniform. Although there are many numerical models that simulate precipitation redistribution processes, the rainwater concentrated by stemflow is usually disregarded. In this study, we performed detailed observations of soil water dynamics during a storm event and developed a three-dimensional model of the effect of stemflow on soil water dynamics around a tree on a forested hillslope. In the stemflow infiltration process, water flowed rapidly through a deep layer, causing irregular changes in the vertical soil water content. This process is very different from the vertical rainfall infiltration process, in which the wetting front expands slowly from the upper layer to the deeper layer. Thus, simulations using the conventional net precipitation input assumption are likely to contain large errors as a result. The model proposed in this study, which considered the point input characteristic of stemflow and parameterized stemflow as a source flux spring in the soil layers, showed adequate spatial and temporal variations in soil water dynamics and closely agreed with observations. Applying the variable source term in the Richards equation to stemflow is a new approach and makes it possible to represent the root-induced bypass flow infiltration process around a tree growing on a hillslope.

Much research has been done since the concept of ecosystem services was put forward. However, activities have concentrated on the larger (global or national) scale, and fragile agroecosystems disturbed by human activity, such as that of the Loess Plateau where decay of the ecological environment occurs through severe soil erosion and harsh natural conditions, have scarcely been considered. Using various parameters such as market value, shadow price and opportunity cost, the authors have calculated the value of agricultural ecosystem services in Ansai county in the Loess region, to include conserving soil (Es) and water (Ew), fixing CO2 and releasing O2 (Ea), maintaining nutrient cycling (En) and decontaminating the environment (Ee). The results show that the gross value of services from the ecosystem is Yuan31,699 million, which is 170 times the production value (Ep). This implies that even this fragile ecosystem has an important support function, although it has been disregarded for a long time. In Ansai county, the agro-ecosystem provides great ecological support for economic productivity. The value of the various contributions to ecological services is, for En, Yuan (RMB)28,481 million (89.8%), for Ew, RMB1,391 million (4.4%), for Ea, RMB1,325 million (4.2%) for Vp, RMB185 million (0.6%), for Es, RMB258 million (0.8%) and for Ee, RMB57 million (0.2%). Moreover, the results show that there is an imbalance between ecological productivity and economic productivity in this area, which is a general problem across the entire Loess Plateau. The first priority for restoring the ecological environment is to extend the areas of grassland and forest in order to improve conservation of soil and water.

Precipitation in a forest is intercepted by the canopy and partitioned into throughfall and stemfl ow, leading to heterogeneous water inputs that affect soil water dynamics. To clarify the effects of a tree stand on rainfall infi ltration processes on a steep forested hillslope, we conducted detailed observations of throughfall, stemfl ow, soil water content, and pore water pressure at high spatial resolution for many storm events. The results showed that the soil water content increased rapidly and greatly in the region downslope from the tree stem, especially at points close to the tree stem. At these points, maximal soil water storage was >100 to 200% of the cumulative open-area rainfall, and occurrences of bypass fl ow were recognized. Moreover, the pore water pressure at the soil‐bedrock interface increased more rapidly and to a greater degree in the region downslope from the tree stem than in the upslope region. For a heavy storm event, the cumulative stemfl ow per infi ltration area along the downslope sides of the tree trunk was 18.9 times the cumulative open-area rainfall. Locally concentrated rainwater input attributable to the stemfl ow on the downslope side of the tree trunk probably caused the large and rapid increases in water content and pore water pressure in the downslope region, resulting in the development of an asymmetric saturated zone around the tree.

To evaluated the fundamental role of stage control technology (SCT) on the detectability for Salmonella networking laboratories.Appropriate Salmonella detection methods after key point control being evaluated, were establishment and optimized. Our training and evaluation networking laboratories participated in the World Health Organization-Global Salmonella Surveillance Project (WHO-GSS) and China-U.S. Collaborative Program on Emerging and Re-emerging infectious diseases Project (GFN) in Shanghai. Staff members from the Yunnan Yuxi city Center for Disease Control and Prevention were trained on Salmonella isolation from diarrhea specimens. Data on annual Salmonella positive rates was collected from the provincial-level monitoring sites to be part of the GSS and GFN projects from 2006 to 2012.The methodology was designed based on the conventional detection procedure of Salmonella which involved the processes as enrichment, isolation, species identification and sero-typing. These methods were simultaneously used to satisfy the sensitivity requirements on non-typhoid Salmonella detection for networking laboratories. Public Health Laboratories in Shanghai had developed from 5 in 2006 to 9 in 2011, and Clinical laboratories from 8 to 22. Number of clinical isolates, including typhoid and non-typhoid Salmonella increased from 196 in 2006 to 1442 in 2011. The positive rate of Salmonella isolated from the clinical diarrhea cases was 2.4% in Yuxi county, in 2012. At present, three other provincial monitoring sites were using the SBG technique as selectivity enrichment broth for Salmonella isolation, with Shanghai having the most stable positive baseline.The method of SCT was proved the premise of the network laboratory construction. Based on this, the improvement of precise phenotypic identification and molecular typing capabilities could reach the level equivalent to the national networking laboratory.

The complex of the cyclic AMP receptor protein (CRP) and cAMP is an important transcriptional regulator of numerous genes in prokaryotes. The transport of mannitol through the phosphotransferase systems (PTS) is regulated by the CRP-cAMP complex. The aim of the study is to investigate how the CRP-cAMP complex acting on the mannitol PTS operon mtl of the Vibrio cholerae El Tor biotype.The crp mutant strain was generated by homologous recombination to assess the need of CRP to activate the mannitol PTS operon of V. cholerae El Tor. Electrophoretic mobility shift assays (EMSA) and the reporter plasmid pBBRlux were used to confirm the role that the CRP-cAMP complex playing on the mannitol PTS operon mtl.In this study, we confirmed that CRP is strictly needed for the activation of the mtl operon. We further experimentally identified five CRP binding sites within the promoter region upstream of the mannitol PTS operon mtl of the Vibrio cholerae El Tor biotype and found that these sites display different affinities for CRP and provide different contributions to the activation of the operon.The five binding sites collectively confer the strong activation of mannitol transfer by CRP in V. cholerae, indicating an elaborate and subtle CRP activation mechanism.