Habitat use by a freshwater dolphin in the low‐water season

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Evaluation of a new management scheme for Norwegian Atlantic salmon Salmo salar

Atlantic salmon, Salmo salar L., stocks are decreasing worldwide, and major efforts are underway to conserve populations that are threatened. In a recent effort to conserve the Norwegian salmon, the Norwegian government implemented in 2007 a scheme called National Atlantic Salmon Watercourses and Fjords (NASW), where 52 rivers were given special protection. Here, the scheme is described and it is evaluated if and to what extent the scheme has led to changes in management practice. After the implementation of the NASW scheme, fewer plans for development (e.g. hydropower plants, water abstraction, flood and erosion control) at the within‐river level were accepted for NASW‐rivers than for rivers not in the scheme. However, at the same time, there was a tendency for fewer plans overall being sanctioned in all types of rivers probably due to overall changes in management practices not related to the NASW scheme. In total, these changes could lead to increased protection of Norwegian Atlantic salmon populations.     

基于支持向量机遥感图像融合分类方法研究进展

总结了近年来国际上图像融合以及支持向量机的应用的研究进展,分析了支持向量机用于遥感图像融合分类的趋势、优势以及目前存在的问题,指出了该研究领域的研究方向。     

天然植物蛋白粉的制取及其研究

由棉籽饼经脱毒、水解、脱味、脱色等工艺而制成的天然植物蛋白粉,其蛋白质含量高,是一种很好的植物蛋白源.该蛋白粉具有良好的发泡性能,使用范围广泛,社会效益和经济效益均十分显著.     

The importance of freshwater flows over estuarine mudflats for wintering waders and wildfowl

The attraction of wintering waterbirds to freshwater flowing over intertidal mudflats of estuaries was studied between 1996 and 1998. This was a response to the increasing levels of freshwater abstraction around internationally protected estuaries in the UK, as its relevance to waterbirds was largely undocumented. The numbers and densities of waterbirds in corridors around freshwater flows were consistently greater than those on the remaining mudflats at all estuaries studied. Large proportions of the estuary populations of several species sometimes occurred around flows. The attraction of freshwater on mudflats to waterbirds, especially ducks and geese, is probably attributable to the presence of water for preening and drinking close to their feeding grounds. Microclimate and shelter may be enhanced, and prey density or availability may be increased for foraging birds on wet mudflats. The amount of freshwater in flows was important to several species and greater densities occurred around larger discharges although very large discharges across narrow mudflats created deep, incised creeks that were unsuitable for most waterbirds. Thresholds of discharge attractive to birds are likely to be estuary-specific and depend on the width of mudflat if freshwater is to reach mid and lower shores at low tide. Surrounding landscapes also influenced the variability of discharge and therefore the predictability of flows. The impact on birds from freshwater abstraction may be similar to effects of displacement from other intertidal grounds and could affect large numbers of birds. The potential impact on bird populations should be included in assessments wherever there are proposals to alter or remove discharges within estuaries.     

鸡蛋黄中提取卵磷脂的最佳工艺条件

采用3因素正交试验从鸡蛋黄中提取卵磷脂,结果表明,提取卵磷脂的最佳工艺为:用分析纯丙酮,丙酮用量与蛋黄之比(mL/g)为3 : 1,静置15 min,得到滤渣丙酮粉,再用浓度99.7 % 的乙醇溶解丙酮粉,温度40 ℃,用量为每克丙酮粉用9.5 mL乙醇。     

基于SCS-CN模型的紫色土坡地径流预测

地表径流是引起坡面土壤侵蚀的主要动力,对降雨径流进行有效的预测,是紫色土坡地水土保持的基础。SCS-CN模型中的径流曲线数CN和初损系数λ作为主要输入参数对径流模拟精度有重要影响,但在应用于紫色土坡耕地模拟时,却很少进行坡度的调整,而坡度是影响降雨产流的重要因子。该文利用紫色土不同坡度的径流小区,选取2013年的5场降雨产流的实测数据,旨在分析紫色土坡耕地降雨产流量与地表坡度的关系,对现有的基于坡度修正的SCS-CN模型进行适用性评价,并在考虑降雨量影响的基础上对初损系数进行修正。结果表明,次降雨下径流量随坡度的增大而增大,并出现径流影响的临界坡度;经坡度修正后的模型在小降雨事件下的模拟精度较好,但强降雨条件下预测值比实测值均偏大,初损系数λ=0.2适用于紫色土坡地小降雨产流模拟,在强降雨条件下,λ值越大,模型模拟效果越好,当λ=0.3时,修正的模型在紫色土坡地径流模拟效果最理想,此时,模拟值与实测值的平均相对误差为7.42%,模型效率系数达到0.99。而基于坡度调整后的CN值对应坡度6.5°~25°依次为78.23、78.45、78.77、79.11、79.47。该研究结果可为紫色土丘陵区降雨径流预测及水土保持提供参考。     

The water needed for Italians to eat pasta and pizza

Water resources use in agriculture is generally quantified in relation to the harvest. In contrast, this paper takes a consumer perspective by assessing water use in relation to the final consumer product. The paper analyses the water use related to two products that are typical to Italian consumers: pasta and pizza margherita. We use the water footprint concept as a tool to quantify and localise this water use. The water footprint of a product is the volume of freshwater used to produce the product, measured over the various steps of the production chain. We find that the water footprint of dry pasta made in Italy amounts to 1924 l of water per kilogram of pasta. The water footprint of a 725 g pizza margherita is 1216 l of water. The impacts of the water footprints of pasta and pizza depend on the vulnerability of the water systems where the footprints are located. The impact of the water footprint of pasta is most severe in Puglia and Sicily, where groundwater overexploitation for durum wheat irrigation is common. The impact of the water footprint of pizza is more diverse. It is concentrated in the first step of the supply chain of tomato puree and mozzarella, i.e. in the cultivation of tomatoes and the feed crops of dairy cows. The bread wheat used for the pizza base does not have large impacts. The water footprint impact of the tomato puree on the pizza is concentrated in Puglia (groundwater overexploitation and pollution related to tomato cultivation) and Emilia-Romagna (water pollution). The water footprint impact of mozzarella lies mostly in the effects of water use for producing the feed ingredients for the dairy cows. Mozzarella production further poses a potential threat to water quality, mostly in the Po valley, but this problem seems to be properly regulated, although possibly not fully controlled.