Based on the crop trial data during 1981-2009 at 57 agricultural experimental stations across the North Eastern China Plain (NECP) and the middle and lower reaches of Yangtze River (MLRYR), we investigated how major climate variables had changed and how the climate change had affected crop growth and yield in a setting in which agronomic management practices were taken based on actual weather. We found a significant warming trend during rice growing season, and a general decreasing trend in solar radiation (SRD) in the MLRYR during 1981-2009. Rice transplanting, heading, and maturity dates were generally advanced, but the heading and maturity dates of single rice in the MLRYR (YZ_SR) and NECP (NE_SR) were delayed. Climate warming had a negative impact on growth period lengths at about 80% of the investigated stations. Nevertheless, the actual growth period lengths of YZ_SR and NE_SR, as well as the actual length of reproductive growth period (RGP) of early rice in the MLRYR (YZ_ER), were generally prolonged due to adoption of cultivars with longer growth period to obtain higher yield. In contrast, the actual growth period length of late rice in the MLRYR (YZ_LR) was shortened by both climate warming and adoption of early mature cultivars to prevent cold damage and obtain higher yield. During 1981-2009, climate warming and decrease in SRD changed the yield of YZ_ER by -0.59 to 2.4%; climate warming during RGP increased the yield of YZ_LR by 8.38-9.56%; climate warming and decrease in SRD jointly reduced yield of YZ_SR by 7.14-9.68%; climate warming and increase in SRD jointly increased the yield of NE_SR by 1.01-3.29%. Our study suggests that rice production in China has been affected by climate change, yet at the same time changes in varieties continue to be the major factor driving yield and growing period trends.
HIGHLIGHTS-Current practice for managing nitrogen (N) use for cereal production are not environmentally sustainable. Over-use of N fertilizers is a global problem for millions of farmers who must decide on N applications-whether, when and how much.-A combination of improved advice on N management for specific cropping regimes is required, together with a breeding target of new commercial crop varieties with sustainable yields and a low N requirement.-While N use efficiency (NUE) has been a useful concept for quantifying the genetic differences in N uptake and utilization, the concept of an economic N optimum derived from N yield dose-response curves may provide new insights for lowering the N requirement Highlights
Spinal gastrin-releasing peptide receptor-expressing (GRPR+) neurons play an essential role in itch signal processing. However, the circuit mechanisms underlying the modulation of spinal GRPR+neurons by direct local and long-range inhibitory inputs remain elusive. Using viral tracing and electrophysiological approaches, we dissected the neural circuits underlying the inhibitory control of spinal GRPR+neurons. We found that spinal galanin+GABAergic neurons form inhibitory synapses with GRPR+neurons in the spinal cord and play an important role in gating the GRPR+neuron-dependent itch signaling pathway. Spinal GRPR+neurons also receive inhibitory inputs from local neurons expressing neuronal nitric oxide synthase (nNOS). Moreover, spinal GRPR+neurons are gated by strong inhibitory inputs from the rostral ventromedial medulla. Thus, both local and long-range inhibitory inputs could play important roles in gating itch processing in the spinal cord by directly modulating the activity of spinal GRPR+neurons.
Despite recent great advances in microbial culture, most microbes have not yet been cultured, and the impact of medium composition on the isolation of microbes from natural systems has not been elucidated. To optimize media for culturing marine microbes, microbial communities in three sediment samples were described using high-throughput sequencing (HTS) and culture-dependent techniques. HTS revealed communities dominated by Gammaproteobacteria, and culture-based methods revealed communities dominated by Actinobacteria. Among the total operational taxonomic units (OTUs) from the HTS dataset, 6% were recovered in the culture collection. Four potentially novel bacterial strains belonging to Oceaniovalibus, Psychrobacter and Salegentibacter were isolated. The combination of media cultured more taxa than any single medium. Nutrient-rich and single-carbon/nitrogen-source media supported the growth of relatively few taxa, and the quality of nitrogen strongly influenced the types of bacteria isolated.
Earthquake-triggered landslides have aroused widespread attention because of their tremendous ability to harm people's lives and properties. The best way to avoid and mitigate their damage is to develop landslide hazard maps and make them available to the public in advance of an earthquake. Future construction can then be built according to the level of hazard and existing structures can be retrofit as necessary. During recent years various approaches have been made to develop landslide hazard maps using statistical analysis or physical models. However, these methods have limitations. This study introduces a new GIS-based approach, using the contributing weight model, to evaluate the hazard of seismically-induced landslides. In this study, the city and surrounding area of Dujiangyan was selected as the research area because of its moderate-high seismic activity. The parameters incorporated into the model that related to the probability of landslide occurrence were: slope gradient, slope aspect, geomorphology, lithology, base level, surface roughness, earthquake intensity, fault proximity, drainage proximity, and road proximity. The parameters were converted into raster data format with a resolution of 25×25m 2 pixels. Analysis of the GIS correlations shows that the highest earthquake-induced landslide hazard areas are mainly in the hills and in some of the moderately steep mountainous areas of central Dujiangyan. The highest hazard zone covers an area of 11.1% of the study area, and the density distribution of seismically-induced landslides was 3.025/km 2 from the 2008 Wenchuan earthquake. The moderately hazardous areas are mainly distributed within the moderately steep mountainous regions of the northern and southeastern parts of the study area and the hills of the northeastern part; covering 32.0% of the study area and with a density distribution of 2.123/ km 2 resulting from the Wenchuan earthquake. The lowest hazard areas are mainly distributed in the topographically flat plain in the northeastern part and some of the relatively gently slopes in the moderately steep mountainous areas of the northern part of Dujiangyan and the surrounding area. The lowest hazard areas cover 56.9% of the study area and exhibited landslide densities of 0.941/km 2 and less from the Wenchuan earthquake. The quality of the hazard map was validated using a comparison with the distribution of landslides that were cataloged as occurring from the Wenchuan earthquake. 43.1% of the study area consists of high and moderate hazardous zones, and these regions include 83.5% of landslides caused by the Wenchuan earthquake. The successful analysis shows that the contributing weight model can be effective for earthquake-triggered landslide hazard appraisal. The model's results can provide the basis for risk management and regional planning is.
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