Effects of salinity on the growth and proximate composition of selected tropical marine periphytic diatoms and cyanobacteria

Marine periphytic cyanobacteria and diatoms have been examined as a potential source of feed supplement for rearing aquatic larvae in the aquaculture industry. Culture of the periphytic diatom Amphora sp., Navicula sp., Cymbella sp. and the cyanobacteria Oscillatoria sp. at different salinities showed significant changes in biomass and specific growth rates. Diatoms growth was significantly higher at 35 g L⁻¹, while for cyanobacteria growth was better at 25 g L⁻¹. Significantly higher levels of protein and lipid were found in diatoms at low salinities (15–25 g L⁻¹) and an increase in carbohydrate at high salinities (30–35 g L⁻¹). Conversely, cyanobacteria showed a significantly higher lipid content at 30–35 g L⁻¹ compared with other salinity levels but no significant changes were observed in the protein and carbohydrate contents at different salinity levels. The present findings can be taken into consideration when culturing marine periphytic Amphora sp., Navicula sp., Cymbella sp. and Oscillatoria sp. to provide appropriate levels of protein, lipid and carbohydrate as feed supplement as well as for bioremediation in aquaculture.     

无孔小咽属线虫2个新记录种的报道

2008年在采集到的胶南市蓝莓(Vaccinium corymbosum L.)根际土中,分离鉴定出无孔小咽属2个中国新记录种,分别为非同无孔小咽线虫Aporcelaimellus alius和食淀粉无孔小咽线虫A.amylovorus。其中,非同无孔小咽线虫A.alius的鉴定特征是雌虫虫体强壮,唇区缢缩明显,角质层由明显的两层组成,阴唇骨化明显,尾长是肛门处体宽的0.7～0.8倍;食淀粉无孔小咽线虫A.amylovorus的鉴定特征是虫体中等,唇区缢缩明显,角质层光滑,由两层构成,雌虫阴唇骨化明显,尾长是肛门处体宽的0.9～1.1倍。     

Changes of Intramuscular Fat Composition,Lipid Oxidation and Lipase Activity in Biceps femoris and Semimembranosus of Xuanwei Ham During Controlled Salting Stages

Fatty acid composition of neutral lipids （NLs）, phospholipids （PLs） and free fatty acids （FFAs） from intramuscular fat （IMF）, lipid oxidation and lipase activity in muscle Semimembranosus （SM） and msucle Biceps femoris （BF） of dry-cured Xuanwei ham during the 90-d salting stages were analysed. The salt content increased from 0.34 to 3.52%in BF and from 0.10 to 5.42%in SM during the 90 d salting stage, respectively. PLs of IMF in both BF and SM decreased 54.70%（P〈0.001） and 34.64%（P〈0.05）, furthermore, the saturated fatty acids （SFA）, monounsaturated fatty acids （MUFA） and polyunsaturated fatty acids （PUFA） of PLs in both muscles were hydrolysed almost isochronously. FFAs were increased from 0.46 g 100 g-1 lipids to 2.92 g 100 g-1 lipids in BF at the end of salting, which was lower than SM （from 1.29 g 100 g-1 lipids to 9.70 g 100 g-1 lipids）. The activities of acid lipase, neutral lipase and acid phospholipase all remained active in the 90 d. The thiobarbituric acid reactive substances （TBARS） was slowly increased to 1.34 mg kg-1 muscle in BF and to 2.44 mg kg-1 muscle in SM during the salting stage. In conclusion, the controlled salting process prompted the hydrolysis of PLs of IMF notably and increased the lipid oxidation of muscles within some limits.     

泗阳县玉米测土配方施肥试验

为明确测土配方技术在泗阳地区玉米生产过程中的实际效果，通过田间试验对玉米生育期、产量构成和效益等进行了对比分析。试验结果显示：采用14.8-9-8的肥料配比能显著提升玉米肥料利用率，提高产量和收益。相较常规施肥，测土配方施肥对玉米生育期影响较小，但玉米穗粒数和千粒重提升效果显著，分别提升了1.88%和3.89%；测土配方施肥的氮、磷、钾肥利用率和养分平均利用率分别为40.77%、28.02%、51.18%，相较常规施肥分别提升了11.55%、4.07%、21.46%，养分平均利用率提升了12.36%；测土配方施肥籽粒产量为9535.04kg/ha，相较常规施肥增产429.99kg，增产率为4.72%，纯收益每公顷提升1269.60元。     

饮水温度对崂山奶山羊产奶性能的影响

为了研究在寒冷季节饮水温度对崂山奶山羊产奶量及主要乳成分的影响,给奶山羊饮用16、22、28℃的温水,以自然水温为对照,结果发现:奶山羊的饮水量和产奶量随水温升高而增加,从低到高其产奶量比CK组产奶量分别显著提高16.2%、18.4%、23.1%(P<0.05);随饮水温度升高,乳脂率和乳蛋白率整体呈现递减趋势,但22℃组高于16℃组和28℃组,建议在冬季寒冷季节给奶山羊饮用22℃温水为宜,既能保证产奶量又对乳品质影响较小。     

Direct impacts of recent climate warming on insect populations

Effects of recent climate change have already been detected in many species, and, in particular, in insects. The present paper reviews the key impacts of global warming on insect development and dispersal. The effects of climate change appear to be much more complex than a simple linear response to an average increase in temperature. They can differ between seasons and bioclimatic regions. Earlier flight periods, enhanced winter survival and acceleration of development rates are the major insect responses. Differential response of insects and hosts to warming up might also lead to disruption of their phenological synchrony, but adaptive genetic processes are likely to quickly restore this synchrony. In a number of cases, warming results in removing or relocating the barriers that limit present species' ranges. It is also likely to facilitate the establishment and spread of invasive alien species. Finally, knowledge gaps are identified and future research interests are suggested.     

宁夏干旱区露地礼品西瓜适应性栽培性状的比较

对8个礼品西瓜品种的植物学性状、抗病性、产量及品质等性状进行了比较试验。结果表明:"黑美人"、"新金兰"不仅抗病、丰产,品质较好,而且产量均超过3 800kg/667m2,在宁夏干旱区露地栽培具备推广价值。     

Long-Term Effect of Fertilizer and Rice Straw on Mineral Composition and Potassium Adsorption in a Reddish Paddy Soil

Increasing K⁺ adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might change K⁺ adsorption because of changes in the chemical and mineralogical properties of a rice (Oryza sativa L.). The aims of this study were (i) to determine clay minerals in paddy soil clay size fractions using X-ray diffraction methods and a numerical diagram-decomposition method; (ii) to measure K⁺ adsorption isotherms before and after H₂O₂ oxidation of organic matter, and (iii) to investigate whether K⁺ adsorption is correlated with changes in soil chemical and mineral properties. The 30-yr long-term fertilization treatments caused little change in soil organic C (SOC) but a large variation in soil mineral composition. The whole-clay fraction (<5 μm) corresponded more to the fertilization treatment than the fine-clay fraction (<1 μm) in terms of percentage of illite peak area. The total percentage of vermiculite-chlorite peak area was significantly negatively correlated with the total percentage of illite peak area in the <5 μm soil particles (R=-0.946, P<0.0006). Different fertilization treatments gave significantly different results in K⁺ adsorption. The SOC oxidation test showed positive effects of SOC on K⁺ adsorption at lower K⁺ concentration (?120 mg L^?1) and negative effects at higher K⁺ concentration (240 mg L^?1). The K⁺ adsorption by soil clay minerals after SOC oxidization accounted for 60–158% of that by unoxidized soils, suggesting a more important role of soil minerals than SOC on K⁺ adsorption. The K⁺ adsorption potential was significantly correlated to the amount of poorly crystallized illite present (R=0.879, P=0.012). The availability of adsorbed K⁺ for plant growth needs further study.