Effects of fertiliser applications on survival and recruitment of the apple snail,Pomacea canaliculata (Lamarck)

Since its introduction to Asia in the 1980s, the golden apple snail, Pomacea canaliculata (Lamarck), has represented a major constraint to the profitability of rice (Oryza sativa L.) farming by damaging rice seedlings during crop establishment. This study describes a series of experiments designed to determine the effects of nitrogenous fertilisers on snail fitness. We examined the possibility of a two-phase model of snail response to nitrogen, whereby fertilisers initially increase snail mortality through toxicity, but once assimilated into the rice ecosystem, eventually favour snail reproduction and survival. In experimental arenas, fertiliser had lethal effects: Complete fertiliser (14:14:14), urea, ammonium sulphate and organic fertilisers were associated with snail mortality, generally affecting adult snails more than juvenile snails, and with greater effects when applied to saturated soil that was subsequently flooded (as opposed to direct application to flooded soil). Snail mortality was found to decline considerably when snails were added to arenas one day after fertiliser application – this occurred in arenas with soil and water, but not in arenas with water only, suggesting that soil can reduce the toxic effects of fertilisers. In a field experiment, snail numbers declined in both fertilised and non-fertilised plots at the time of crop establishment. Numbers increased in all plots after rice tillering, with significantly more recruitment in plots with high nitrogen. Although the responses were generally weak in the field experiment, they did support the two-phase model. The consequences of fertiliser applications for snail management and ecosystem health are discussed.     

海洋养殖生物体中石油烃含量分布及变化情况研究

根据2005～2007年三年来福建沿海养殖生物体中的石油烃(TPH)检测数据,对鱼类、贝类、甲壳类删含量的分布和变化进行研究.海洋养殖生物体Ⅱ'H含量范围在(1.00～179.71)×10-6湿重,总平均值为10.60×10-6湿重.TPH总体平均含量年份变化:2006年>2007年>2005年;海洋养殖生物体部分类别差异:贝类>甲壳类>鱼类;贝类中缢蛏含量最高,鲍含量最低;贝类体中胃含物>肌肉组织>体液.平均TPH污染指数<1,总体属轻度污染.     

虾池基础生物饵料的培养技术及其种类,数量的研究

为解决虾苗入池后的前期饵料，降低养虾成本，对对虾美成池基础生物饵料的培养技术及其种类，数量进行了研究。对试验池２４０个水样进行生物定性，定量分析的结果：浮游植物有７４种，隶属７门８纲４１属；浮游动物有５３种，隶属７纲１４目；平均生物量为７４．４７×１０＾６个／Ｌ或３８．３９ｍｇ／Ｌ。基础生物饵料的种类和数量随着水温的升高而增多。通过合理施肥使池水保持自然生态平衡，不用投喂任何代用饲料，便可使对虾长     

Detection of mycoplasmalike organisms in declining oaks by polymerase chain reaction

By polymerase chain reaction, mycoplasmalike organisms (MLOs) were detected in several declining trees of Quercus robur sampled at two locations of Germany. The MLOs associated with declining oaks were, within the 16S rDNA studied, genetically uniform and closely related to the MLOs associated with European stone fruit yellows and apple proliferation.     

海晏牧场草地畜牧业最适载畜量的研究

根据青海省海晏牧场的草地资源，畜牧业生产特点，对草地畜牧业最适载畜量进行了研究。结果表明，不同放牧强度对夏秋草地和冬春草地地上生物量均有不同程度的影响，试验组与对照组对比，Ａ、Ｂ两组生物量分别下降了２５．６６％，２０．５１％，而Ｃ、Ｄ、Ｅ组分别提高了２６．３９％，２９．４４％，３３．８４％，同时，放牧强度影响草地植被成分和牧草干物质的消化率，由此得出，在不影响草地和家畜生产的前提下，海晏牧场夏秋草     

Pesticide buffer zones for the protection of wildlife

Buffer zones can play important roles in agricultural habitats, both in the protection of off-crop habitats from pesticide and fertiliser drift and run-off, and in providing important areas of non-crop habitats. Their role in the protection of aquatic habitats from pesticide drift is a significant feature of pesticide risk management, but they are currently used only to a limited degree to protect terrestrial habitats. This paper summarises some of the evidence for the risks and impacts of pesticide drift into non-crop habitats, and the approaches taken by the nature conservation agencies in deriving buffer zones for the protection of sites that are important for nature conservation. Biodiversity objectives need to be explicitly built into ICM programmes, and buffer zones, together with appropriate application technology, can play an important part in reducing pesticide drift in ICM systems to achieve such objectives.     

完善有害生物预警系统,促进草地持续发展

分析我国草地有害生物治理面临的形势和预警系统所存在的问题。建议尽快制定生态环境评价标准,以扭转我国草地生态环境恶化的局面。制订生态环境评价标准的原则:(1)草地植被的基本生产力得以保持,具有持续发展的基本功能;(2)草地生物多样性指数,特别是有花植物和野生动物多样性指数处于相对稳定状态;(3)草地畜牧业生产水平与草地生产力相适应;(4)草地经济效益与全国农业效益的平均水平处于同一发展阶段;(5)地方制定的法律、法规与国家基本国策相配套,有利于保护草地环境和牧业生产。有害生物持续控制能力(FA)的迭加计算:FA=∑W_kW_j。式中Wk为一级标准,Wj为二级标准,为属性参数。     

Seaweed-Derived Phlorotannins: A Review of Multiple Biological Roles and Action Mechanisms

Phlorotannins are a group of phenolic secondary metabolites isolated from a variety of brown algal species belonging to the Fucaceae, Sargassaceae, and Alariaceae families. The isolation of phlorotannins from various algal species has received a lot of interest owing to the fact that they have a range of biological features and are very biocompatible in their applications. Phlorotannins have a wide range of therapeutic biological actions, including antimicrobial, antidiabetic, antioxidant, anticancer, anti-inflammatory, anti-adipogenesis, and numerous other biomedical applications. The current review has extensively addressed the application of phlorotannins, which have been extensively investigated for the above-mentioned biological action and the underlying mechanism of action. Furthermore, the current review offers many ways to use phlorotannins to avoid certain downsides, such as low stability. This review article will assist the scientific community in investigating the greater biological significance of phlorotannins and developing innovative techniques for treating both infectious and non-infectious diseases in humans.     

转基因生物对生物多样性影响的研究进展

随着转基因生物,尤其是转基因作物的不断推广,转基因生物对生物多样性的影响受到越来越多的关注。本文论述了近年来转基因生物对植物、动物以及微生物生物多样性影响的研究进展。     

Characteristics of the temperature coefficient, Q 10, for the respiration of non-photosynthetic organs and soils of forest ecosystems

The temperature coefficient, Q ₁₀ (fractional change in rate with a 10°C increase in temperature) describes the temperature sensitivity of soils, roots, and stems, as well as their possible performance in global warming processes. It is also a necessary parameter for the estimation of total CO₂ efflux from each element. A number of studies have focused on Q ₁₀ values to date; however, their conclusions are not universal and do not always agree. A review of these reported Q ₁₀ values therefore becomes necessary and important for a global understanding of the temperature sensitivity of different forest types and elements. The aims of our present paper are, first, to find the frequency distribution pattern of soils, roots, and stems (branches) and compare their temperature sensitivity; then, to find the Q ₁₀ differences between conifer and deciduous tree species and the effect of methodology on Q ₁₀ values; finally we want to give a perspective on future Q ₁₀-related studies. We found that most Q ₁₀ values of each element were concentrated in a relatively narrow range despite a total data distribution over quite a wide range. For soil respiration, the median Q ₁₀ value was 2.74 and the center of the frequency distribution was between 2.0 and 2.5 with a percentage of 23%. Most of the data (>80%) were within the range from 1.0 to 4.0. The median Q ₁₀ value for root respiration was 2.40 and the center of the frequency distribution was from 2.5 to 3.0 with a percentage of 33%. Most of the results (>80%) ranged from 1.0 to 3.0. For stem respiration, the median Q ₁₀ value was 1.91 and the frequency distribution was concentrated between 1.5 and 2.0. Over 90% of the data ranged from 1.0 to 3.0. Obvious differences in Q ₁₀ value were found between different elements, stem < root < soil including root < soil excluding root. The differences between woody organisms of stems, roots, and soils excluding roots were statistically significant (p<0.05), indicating that heterotrophic respiration from microorganism activity may be more sensitive to global warming. The duration of the period with leaves slightly affects the temperature sensitivity of woody organisms since the Q ₁₀ values for root and stem of coniferous evergreen trees did not differ significantly from deciduous trees (p>0.10). CO₂ analytical methods (soda lime absorption method, IRGA (Infra-read gas analysis), and chromatograph analysis) and root separation methods (excised root and trenched box) slightly affected the Q ₁₀ values of soil and root respiration (p>0.10), but an in vitro measurement of stem respiration yielded a significantly higher Q ₁₀ value than an in vivo method (p<0.05). In general, although the Q ₁₀ values of non-photosynthetic organisms stayed within a relatively conservative range, considerable variation between and within elements were still detectable. Accordingly, attention should be paid to the quantitative estimation of total CO₂ efflux by Q ₁₀-related models. In future studies, the biochemical factors and the environmental and biological factors controlling respiration should be emphasized for precise estimation of total CO₂ efflux. The difficulty is how to clarify the underlying mechanism for fluctuations of Q ₁₀ values for one specific habitat and element (e.g. temperature acclimation or adaptation of Q ₁₀ values) and then allow the Q ₁₀ values to be more conservative for representation of temperature sensitivity in global warming processes. __________ Translated from Acta Phytoecologica Sinica, 2005, 29(4) [译自:植物生态学报, 2005, 29 (4)]