大麦籽粒蛋白质含量的研究进展

综述了大麦籽粒蛋白质组分,籽粒蛋白质含量的遗传特性等方面的研究进展,并对气候与环境条件对大麦籽粒蛋白质含量的影响做了介绍。这些研究报道,可为优质大麦的生产和育种提供借鉴。     

Establishing larval feeding regimens for the Forktail Blenny Meiacanthus atrodorsalis (Günther, 1877): effects of Artemia strain,time of prey switch and co‐feeding period

This study aimed to establish feeding strategies covering the whole larval period of the forktail blenny, Meiacanthus atrodorsalis, based on the standard hatchery feeds of rotifers and Artemia. Three purposely designed experiments were conducted to determine the appropriate times and techniques to transition larvae from rotifers onto Artemia nauplii of a Great Salt Lake (GSL) strain, and a specialty AF strain, as well as subsequent transition onto enriched metanauplii of GSL Artemia. With a 3‐day co‐feeding period, larvae adapted well to a transition from rotifers to newly hatched GSL Artemia nauplii as early as 5 days posthatching (DPH), and as early as 3 DPH when fed the smaller AF Artemia nauplii. However, prolonging the rotifer‐feeding period up to 11 DPH did not negatively affect survival. Larvae fed Artemia nauplii of the AF strain showed 17–21% higher survival, 24–33% greater standard length and body depth, and 91–200% greater dry weight, after 20 days relative to those fed nauplii of the GSL strain. Meanwhile, enriched Artemia metanauplii of the GSL strain were shown to be an acceptable alternative to AF Artemia nauplii for later larvae, producing similar survival and growth when introduced from 8 DPH. Based on our findings, we recommend feeding M. atrodorsalis larvae rotifers as a first food between 0 and 2 DPH, introducing AF Artemia nauplii from 3 DPH, followed by enriched GSL Artemia metanauplii from 8 DPH onward, with a 3‐day co‐feeding period between each prey change.     

基于模糊评价法的洱海稳态阶段分析

稳态转化理论被广泛应用于各种系统的变化,也常常用于描述水生和陆生生态系统状态发生本质、渐进和持续的转变过程。对淡水湖泊生态系统而言,研究其变化过程及驱动因子将有助于理解当前水环境问题的本质特征,为水环境整治与生态修复提供理论支撑。为了确定典型高原湖泊洱海所处的稳态阶段及其转换取向,在野外调查研究及文献资料数据分析的基础上,尝试用模糊评价法分析洱海所处的稳态转换阶段。评价结果表明,洱海1985-2001年处于清水稳态,2002年系统发生跃迁,2003年退化到藻草共存、草藻共存的过渡态。从2009-2010年     

Guidelines for incorporating fish distribution shifts into a fisheries management context

The impacts of climate change have been demonstrated to influence fisheries resources. One way climate has affected fish stocks is via persistent shifts in spatio‐temporal distribution. Although examples of climate‐forced distribution shifts abound, it is unclear how these shifts are practically accounted for in the management of fish stocks. In particular, how can we take into account shifting stock distribution in the context of stock assessments and their management outputs? Here, we discuss examples of the types of fish stock distribution shifts that can occur. We then propose a decision tree framework of how shifting stock distributions can be addressed. Generally, the approaches for addressing such shifts fall into one of three main alternatives: re‐evaluate stock identification, re‐evaluate a stock unit area, or implement spatially explicit modelling. We conclude by asserting that the approach recommended here is feasible with existing information and as such fisheries managers should be able to begin addressing the role of changes in stock distribution in these fish stocks. The implications of not doing so could be notably undesirable.     

Global patterns in urban green space are strongly linked to human development and population density

Urban green space is important for alleviating high temperatures, pollution, and flooding in cities. Furthermore, it is becoming increasingly clear that urban green space is important for the mental and physical health of humans residing in cities and that urban green space may harbor unique biodiversity. Understanding the extent and drivers of urban green space is thus important. While urban green space has been mapped and studied at local to national scales, the global patterns and drivers of urban green space remain unknown, potentially hampering effective planning and allocation of resources toward reaching sustainable development goals. Here, we quantified the effect of environmental and socio-economic drivers (temperature, precipitation, human development, and population density) on urban green space globally by focusing on national capital cities. We used satellite imagery to map urban green space using two measures: the Normalized Difference Vegetation Index (NDVI), and the fractional cover of “green” land cover classes. NDVI is useful as it includes all vegetated surfaces, also small ones like gardens. However, land cover classes allow the exclusion of certain classes such as sports fields or cropland. We used boosted regression trees to show that climatic variables accounted for 75 % of the relative influence in urban green space, with a positive effect of precipitation and a negative effect of temperature. Importantly, socioeconomic variables accounted for 25 % of the influence on global urban green space, with a positive effect of human development index (HDI) and a negative effect of population density. HDI in relation to urban green space has not previously been tested globally, and our study shows that significantly affects urban greenspace. The results demonstrate that cities where development status is low and population densities are high, typically in the Global South, have less urban green space than the climate would predict. The results therefore suggest that human wellbeing does not only benefit directly from increasing human development and decreasing population densities in urban areas, but that these effects may be compounded by also improving nature’s contribution to people.     

From carbon flux to regime shift

The basic assumption in biological oceanography – and in GLOBEC – is that physical forcing at a wide range of space and time scales determines most of the dynamics of marine populations. This has been very productive and provides the global context for GLOBEC and other programmes. How far can it take us in the future; and, alternatively, what role is played by community interactions?     

“甜樱桃”跨气候带引种栽培研究

2010年开始,从山东等温带地区引进了12个“甜樱桃”新品种,在汉中北亚热带气候条件下种植,对其适应性、开花、着果、成熟期、口感等方面进行了试验研究。并以适应性、早熟性等综合性状为目标,筛选出了在口感、抗逆性、着色、丰产等方面表现良好的早、中熟品种7个,可适宜于广泛种植的早熟、矮化品种3个,为汉中甜樱桃产业发展提供了参考。     

Climate change and soil erosion on agricultural land in england and wales

To assess the effects of climate change on soil erosion we need to model changes in rate, frequency and extent of erosion. Present day rates of soil erosion for agricultural land in England and Wales are known from a national monitoring scheme and also from a local one. The latter, for the South Downs, covers a seven-year period and includes climatic data. This shows a strong correlation between total erosion and a Rainfall Index. The availability of these databases allows us to use existing models such as EPIC and an Expert System to predict erosion rates for postulated warmer and wetter (winter) conditions. EPIC is particularly suitable for specific sites where detailed data exists and crop yield implications can also be modelled. A rule-based Expert System approach allows us to examine erosion rates at a different scale across the landscape. We postulate that water erosion rates on arable land in the lowlands will increase markedly in severity, frequency and extent especially if land use changes. In the uplands predicted climatic warming suggests a longer growing season and fewer frosts: these may lead to a decrease in erosion of overgrazed eroding slopes. Increases in erosion rates are not inevitable if policy decisions are taken and implemented in good time.     

山地小气候模型在帽儿山地区气候模拟中的应用

利用山地小气候模拟模型(MTCLIM)对帽儿山地区气候进行了模拟,由已测数据作为输入变量,对帽儿山张家沟集水区2002年最冷月均温、最热月均温、降水量、蒸散发等进行了模拟估算,结果表明:高海拔地区年积温低于低海拔地区,符合随海拔高度的增加温度降低的一般规律;最冷月均温、最热月均温分布规律与积温的分布规律相吻合,它们的空间分布与地形变化基本上是一致的。但是由于植被因素的作用,潜在蒸散量略有不同。用帽儿山气象站1989—2001年实测数据对模拟结果进行验证,两者数据基本符合。将MTCLIM模型与GIS技术相结合,采用不同的垂直递减率,运用Kringing方法对气象因子的时间、空间分布的模拟,不仅可以了解温度、降水、辐射等因子的分布情况,还可以为生态学过程研究奠定坚实的基础,同时也可以为植被动态模型提供气候数据支持,揭示森林植被变化的动态过程,实现森林景观与功能的耦合。     

红壤性水稻田土壤-水-植物系统中毒死蜱的迁移转化和分布特征

为了探究毒死蜱在红壤性水稻田土壤、水、植物系统中的迁移转化和分布特征,通过室内批量平衡吸附实验、野外喷施试验与动态观测,研究了持续淹水和间歇淹水条件下红壤性水稻土-水-水稻系统中毒死蜱的迁移转化和分布特征。结果表明：毒死蜱在呈酸性的红壤性水稻土中易于淋失迁移至深层土壤（可达50 cm）;白昼的高温导致表层土壤孔隙水中毒死蜱及其主要降解产物3,5,6-三氯-2-吡啶醇（TCP）的浓度显著上升,而降雨事件促进两者向深层土壤迁移;水稻收获时土壤中毒死蜱残留量较高,且其剖面分布较为均匀;间歇淹水处理可使收获时水稻籽粒和茎秆中的毒死蜱残留量降低为持续淹水处理水稻相应部位的0.69倍和0.84倍。研究显示,红壤性水稻土壤中毒死蜱的淋溶作用较强,不同的灌溉方式对收获期水稻中毒死蜱的含量有显著影响。