旱地农业高效用水技术的应用研究

旱地农业面积约占全国耕地面积的59％，对国民经济具有举足轻重的作用。旱地农业没有灌溉条件，必须在提高降水利用率上做文章。旱地农业高效用水技术主要包括：适水种植、选育抗旱节水高产品种、搞好农田基本建设、耕作保墒、化学调控节水和抗旱灌溉。     

Towards a Drought Watch System based on Spatial SPI

Regional Drought can be assessed through various meaningfulprocedures mainly related to the expected consequences. However, a general knowledge of the occurrence of drought, thearea which is affected, its severity and its duration are ofgreat importance for a series of decisions, which may beappropriate for a variety of activities. From the existingsimple and popular indices used for the estimation of drought,the Standardised Precipitation Index, known as SPI, seems to winuniversal applicability. A method based on the estimation of SPIover a geographical area and its use for characterising drought,is presented in this paper. Applications of the method arepresented using a digital terrain model and a simple computercalculating routine. It is shown that the proposed procedurecan be easily applied and can support a Drought Watch System foran area of mesoscale dimensions.     

大庆地区水资源可持续发展需要解决的问题

根据大庆地区的自然地理、水资源及水利工程状况，针对各种灾害情况提出相应的对策措施，以实现大庆地区水资源可持续发展。     

A lysimeter study of nitrate leaching, optimum fertilisation rate and growth responses of corn (Zea mays L.) following soil amendment with water-saving super-absorbent polymer

BACKGROUND: Nitrate leaching and the resulting groundwater contamination from intensive cereal production has become a major concern for long‐term farmland efficiency and environmental sustainability in northern China. The aim of this study was to evaluate a water‐saving super‐absorbent polymer (SAP) for minimising NO₃^? leaching from soil and optimising corn growth and yield. Thirty‐six undisturbed soil lysimeters were installed in a field lysimeter facility in drought‐affected northern China to study the growth and yield characteristics of summer corn (Zea mays L.) as well as the amount of NO₃–leaching losses under different fertiliser (standard, medium or 75% and low, or 50% of conventional fertilisation rate) and SAP (control, 0; level‐1, 15 kg ha^?1 and level‐2, 30 kg ha^?1) treatments. RESULTS: Corn yield fell by 19.7% under medium and 37.7% under low fertilisation; the application of SAP increased yield significantly by 44.4% on level‐1 and 80.3% on level‐2. Similarly, plant height, leaf area, number of grains as well as protein, soluble sugar and starch contents in the grain also increased with SAP treatment. Application of SAP at 30 kg ha^?1 plus half of conventional fertilisation can reduce maximum (64.1%) nitrate leaching losses from soil. CONCLUSIONS: Application of SAP at 30 kg ha^?1 plus only half the amount of conventional fertiliser rate (150 kg urea, and 50 kg each of superphosphate and potassium sulfate) would be a more appropriate practice both for minimising nitrate leaching and sustainable corn production under the arid and semiarid conditions of northern China. Copyright © 2011 Society of Chemical Industry     

烟草水分胁迫研究进展

综述了烟草水分胁迫与烟株生长发育、烟株生理变化以及产、质量的关系,并展望了今后的研究方向.     

湖南省水库与干旱情势空间匹配关系研究

根据湖南省地质、地形等条件,以县域为单元将湖南省划分为9个区域,对省内14000多座各类型水库开展空间统计,分析了水库空间分布规律,并采用SPI-3指数法计算得到4-9月重旱及以上干旱频率的空间分布,对比研究了水库分布与干旱的空间匹配关系.结果 表明:湖南省水库分布具有明显的空间分异特征,丘陵区水库数量密度一般要大于山...     

山东省旱灾变化规律及减灾对策

根据山东省实测、调查的干旱灾害资料及历史记载,对干旱灾害进行了综合分析,探索了干旱灾害变化的基本规律,揭示了干旱灾害的成因,提出了抗旱减灾的对策建议。     

Diagnosing anomalous characteristics of atmospheric water cycle structure during seasonal-scale drought events: A case study in middle and lower reaches of Yangtze River

Anomalous characteristics of the atmospheric water cycle structure are highly significant to the mechanisms of seasonal-scale meteorological droughts. They also play an important role in the identification of indicative predictors of droughts. To better understand the causes of seasonal meteorological droughts in the middle and lower reaches of the Yangtze River (MLRYR), characteristics of the atmospheric water cycle structure at different drought stages were determined using standardized anomalies. The results showed that the total column water vapor (TCWV) was anomalously low during drought occurrence periods. In contrast, there were no anomalous signals at the drought persistence and recovery stages in the MLRYR. Moreover, there was no significant temporal correlation between the TCWV anomaly and seasonal-scale drought index (the 3-month standardized precipitation index (SPI₃)). During drought events, water vapor that mainly originated from the Bay of Bengal was transported southwest of the MLRYR. Meanwhile, the anomalous signal of water vapor transport was negative at the drought appearance stage. At the drought persistence stage, the negative anomalous signal was the most significant. Water vapor flux divergence in the MLRYR showed significant positive anomalous signals during drought events, and the signal intensity shifted from an increasing to a decreasing trend at different drought stages. In addition, a significant positive correlation existed between the anomaly of water vapor flux divergence and regional SPI₃. Overall, water vapor flux divergence is more predictive of droughts in the MLRYR.     

Genome-Wide Identification of the CER Gene Family and Significant Features in Climate Adaptation of Castanea mollissima

The plant cuticle is the outermost layer of the aerial organs and an important barrier against biotic and abiotic stresses. The climate varies greatly between the north and south of China, with large differences in temperature and humidity, but Chinese chestnut is found in both regions. This study investigated the relationship between the wax layer of chestnut leaves and environmental adaptation. Firstly, semi-thin sections were used to verify that there is a significant difference in the thickness of the epicuticular wax layer between wild chestnut leaves in northwest and southeast China. Secondly, a whole-genome selective sweep was used to resequence wild chestnut samples from two typical regional populations, and significant genetic divergence was identified between the two populations in the CmCER1-1, CmCER1-5 and CmCER3 genes. Thirty-four CER genes were identified in the whole chestnut genome, and a series of predictive analyses were performed on the identified CmCER genes. The expression patterns of CmCER genes were classified into three trends—upregulation, upregulation followed by downregulation and continuous downregulation—when chestnut seedlings were treated with drought stress. Analysis of cultivars from two resource beds in Beijing and Liyang showed that the wax layer of the northern variety was thicker than that of the southern variety. For the Y-2 (Castanea mollissima genome sequencing material) cultivar, there were significant differences in the expression of CmCER1-1, CmCER1-5 and CmCER3 between the southern variety and the northern one-year-grafted variety. Therefore, this study suggests that the CER family genes play a role in environmental adaptations in chestnut, laying the foundation for further exploration of CmCER genes. It also demonstrates the importance of studying the adaptation of Chinese chestnut wax biosynthesis to the southern and northern environments.     

TaNBR1, a Novel Wheat NBR1-like Domain Gene Negatively Regulates Drought Stress Tolerance in Transgenic Arabidopsis

Drought stress is an important factor that severely affects crop yield and quality. Autophagy has a crucial role in the responses to abiotic stresses. In this study, we explore TaNBR1 in response to drought stress. Expression of the TaNBR1 gene was strongly induced by NaCl, PEG, and abscisic acid treatments. The TaNBR1 protein is localized in the Golgi apparatus and autophagosome. Transgenic Arabidopsis plants overexpressing TaNBR1 exhibited reduced drought tolerance. When subjected to drought stress, compared to the wild-type (WT) lines, the transgenic overexpressing TaNBR1 plants had a lower seed germination rate, relative water content, proline content, and reduced accumulation of antioxidant enzymes, i.e., superoxide dismutase, peroxidase, and catalase, as well as higher chlorophyll losses, malondialdehyde contents, and water loss. The transgenic plants overexpressing TaNBR1 produced much shorter roots in response to mannitol stress, in comparison to the WT plants, and they exhibited greater sensitivity to abscisic acid treatment. The expression levels of the genes related to stress in the transgenic plants were affected in response to drought stress. Our results indicate that TaNBR1 negatively regulates drought stress responses by affecting the expression of stress-related genes in Arabidopsis.