Diving behaviour of Little Penguins from four colonies across their whole distribution range: bathymetry affecting diving effort and fledging success

Little Penguins, Eudyptula minor, breed in several small colonies in New Zealand and Australia. In this study, we compare the birds’ diving performances at different sites situated throughout their breeding range. Environmental conditions and breeding success vary drastically amongst colonies, but all birds feed on similar types of prey and face similar limitations on their foraging range. We examined several diving parameters and calculated the proportion of foraging zone available during breeding to examine whether oceanographic and geographic factors in the foraging zone can explain variations in diving behaviour and fledging success among the different colonies. In colonies with high fledging success, Penguin Island and Oamaru, penguins made shallow dives <50 m depth and had lower diving effort. More than 90% of the foraging zone was in waters <50 m depth in these colonies. Motuara Island also has shallow waters with 95% <50 m depth, but the fledging success was low. Phillip Island has only 42% of waters <50 m and comparatively low fledging success. Thus, penguins dived deeper and showed a higher diving effort in colonies with lower fledging success (Motuara Island and Phillip Island), indicating that they were disadvantaged compared to conspecifics from other colonies that dived shallower and with a lesser diving effort. We concluded that bathymetry is an important factor, but not the only one, which influences fledging success.     

Swim speeds of free-ranging great cormorants

Information about foraging speeds is particularly valuable when the impact of a predator species upon a community of prey has to be defined, as in the case of great cormorants. We measured the swim speed of 12 (six males and six females) free-ranging great cormorants Phalacrocorax carbo, foraging off the Greenland coast during the summer of 2003, using miniaturized data-loggers. Although mean body mass of males was 27% greater than that of females, and mean swim speed of males were 29–57% higher than that of females during foraging phases (but not descent phases) of dives, these differences in speeds were not significant due to high variances. Birds descended to the mean maximum depth of 4.7 m at an average speed of 1.6±0.5 m s⁻¹, a speed similar to that measured in captive cormorants in previous studies. Although bursts of up to 4 m s⁻¹ were recorded, speed usually decreased during the deepest (foraging) phase of dives, being on average 0.8±0.6 m s⁻¹. Speeds measured here should be taken with caution, because the large propeller loggers used to measure speed directly decreased descent speeds by up to 0.5 m s⁻¹ when compared to smaller depth-only loggers. Cormorants in Greenland seem to combine two searching strategies, one requiring low speed to scan the water column or benthos, and one requiring high speed to pursue prey. These two strategies depend on the two main habitats of their prey: pelagic or demersal.     

Impact of photosynthesis and transpiration on nitrogen removal in constructed wetlands

To determine the impact of photosynthesis and transpiration on nitrogen removal in wetlands, an artificial wetland planted with reeds was constructed to treat highly concentrated domestic wastewater. Under different meteorological and hydraulic conditions, the daily changes of photosynthesis and transpiration of reeds, as well as nitrogen removal efficiency were measured. It was found that net photosynthesis rate per unit leaf area was maintained on a high level (average 19.0 μmol CO₂/(m²·s)) from 10:00 to 14:00 in July 2004 and reached a peak of 21.1 μmol CO₂/(m²·s) when Photon Flux Density was high during the day. Meanwhile, TN and NH₄ ⁺-N removal efficiency rose to 79.6% and 89.6%, respectively—the maximum values observed in the test. Correlation coefficient analysis demonstrated a positive correlation among photon flux density, net photosynthetic rate, transpiration rate, and TN and NH₄ ⁺-N removal efficiency. In contrast, there was a negative correlation between stomatal conductance and TN and NH₄ ⁺-N removal efficiency. Results suggest that the photosynthesis and transpiration of wetland plants have a great impact on nitrogen removal efficiency of wetlands, which can be enhanced by an increase in the photosynthesis and transpiration rate. In addition, the efficiency of water usage by reeds and nitrogen removal efficiency could be affected by the water level in wetlands; a higher level boosts nitrogen removal efficiency.     

磷肥施用量对缺锌土壤上水稻生长的影响

磷肥施用量对缺锌土壤上水稻生长的影响李延，潘伟彬（福建农业大学土化系，福州３５０００２）（闽西职业大学，龙岩３６４０２１）ＥｆｆｅｃｔｏｆＰｈｏｓｐｈａｔｉｃＦｅｒｔｉｌｉｚｅｒｏｎＧｒｏｗｔｈｏｆＲｉｃｅｏｎＺｉｎｃＤｅｆｉｃｉｅｎｔＳｏｉｌ￥Ｌｉ...     

对化学品登记要求的数据解释——急性毒性和急性刺激

本文对化学品登记时所要求的部分健康效应数据一急性毒性和急性刺激做了解释.涉及到的测试参数包括:急性经口毒性、急性经皮毒性、急性吸入毒性、急性皮肤刺激/腐蚀和急性眼睛刺激/腐蚀.     

Z198型除尘器在生石灰硝化工程上的应用

对Z198型布袋除尘器的结构、工作原理等作了介绍,并分析了其在生石灰硝化工程中的应用情况及效果,同时指出了在使用过程中存在的问题。     

巢湖流域不同土地利用类型地表径流污染特征研究

巢湖是我国五大淡水湖之一,目前正面临着严重的环境污染与水体富营养化问题。通过对巢湖流域塘西地区大豆地,水稻田,菜地,山芋地,小麦地,集镇街道,山坡地,饲养场地,农村道路,湖滩芦苇地,荒地等１１种土地利用类型地表径流污染现状的详细调查与分析,建立了巢湖流域不同土地利用类型地表径流污染研究的一般程序与方法。     

Te（IV）胁迫对两种螺旋藻生长的影响

对极大螺旋藻(Spirulina maxima)和钝顶螺旋藻(S.platensis),在接种后第1~7 d通过不同时间添加Na2TeO3来施加Te(IV)胁迫,5种Te(IV)胁迫实验组的累计加Te浓度均为250 mg/L,结果表明:两种螺旋藻的最终生物量,从I~V组均呈增加趋势;其中IV、V组对S.platensis的生长有促进作用。利用动力学方程并结合胁迫强度的概念,对实验结果进行了合理的解释。     

垃圾填埋场内部CH4浓度随时间的变化特征及其模拟

通过对沸山市五峰垃圾清现场内部部分时段ＣＨ４浓度的监测，分析了在填埋场内部垃圾发酵过程中ＣＨ４浓度随时间的动态变化特征提出了利用某些统计曲线分别模拟或综合模块ＣＨ４浓度随时间的变化过程的方法，应用表明：本方法可以较准确地预测垃圾发酵主要内的ＣＨ４浓度随时间的变化，仅在垃圾发酵的尾声阶段，模拟浓度与实测浓度有少许出人。     

气体扩散电极制备及其对苯酚降解效果的研究

以质量比9∶1的活性炭和乙炔黑制备气体扩散电极,着重研究电流密度、pH值、曝气量等因素对H2O2产生量的影响.结果表明:pH值在较大范围内均适用;电流密度控制在50～75 mA/cm2,曝气量确定为5 L/min时,反应产生H2O2较多.另外,利用该气体扩散电极做阴极,石墨电极做阳极,以Na2SO4为电解质,研究了电解时间、电流密度、pH值、初始苯酚浓度、曝气量等因素对苯酚降解效果的影响.结果表明:在电流密度为75 mA/cm2、曝气量为5 L/min、初始pH=3的条件下,当苯酚的初始浓度为80 mg/L时,1 h后其去除率达77%.