青岛崂山主要植被类型及物种丰富度研究

为保育恢复青岛崂山主要植被,提高森林覆盖率,采用典型样地法,对青岛崂山现存植被主要类型进行调查,结果表明：崂山地形复杂,气候多样,植物种类繁多,加之人工引种栽培,形成了多样的植被类型,且不同海拔分布着不同的植被类型,其中针叶林分布广泛,主要建群种是赤松(Pinus densiflora);阔叶林主要是有落叶阔叶林构成,主要树种有麻栎(Quercus acutissima)、栓皮栎(Quercus variabilis)等;灌草丛以中生或旱中生多年生草本植物为主要建群种,建群层为草本层;不同海拔,科、属、种丰富度不同,且物种丰富度在中海拔地区较高;北九水,蔚竹庵,太清宫,流清河,凉清河,仰口等地具有较高的物种丰富度,双石屋、冷翠霞、观崂村等样地物种丰富度较低。     

岱衢洋鱼类资源及其群落多样性的季节变化

根据2010年春季(5月)、夏季(8月)、秋季(11月)与2011年冬季(2月)对岱衢洋进行的共4个航次的底拖网渔业资源调查资料, 对该海域的鱼类资源状况及其多样性进行了分析, 结果表明: 所捕获的38种鱼分别隶属于1门2纲8目21科31属; 暖温性鱼类无论在种类数量还是生物量与尾数密度方面均居主导地位; 凤鲚四季均为该海域的优势种; 在时间分布上, 生物量与资源尾数密度均以夏季为最高, 而冬季则恰好相反, 且该两季的生物量与资源尾数密度间均存在显著差异(P<0.05), 另外, 在空间分布上, 生物量与尾数密度四季总体上均呈北高南低、东高西低的趋势; 生物量与平均底层温度呈二次曲线相关(P<0.01); 春、秋两季的Margalef丰富度指数( D )、Shannon-Wiener多样性指数( H' )和Pielou均匀度指数( J' )均存在显著差异(P<0.05); 与东海近、外海海域鱼类群落的多样性比较, 岱衢洋的Shannon- Wiener多样性指数( H' )较低。     

洞头列岛潮间带大型底栖生物的时空分布及其多样性

为了解洞头列岛潮间带大型底栖生物的时空分布特征及其多样性, 分别于2006年秋季(10月)和2007年春季(4月)对洞头列岛4个断面开展了春秋航次调查。共鉴定出大型底栖生物72种, 包括软体动物44种, 甲壳动物13种, 藻类11种, 多毛类2种, 棘皮动物1种, 其它动物1种。从季节来看, 虽秋季航次的物种数(66种)稍高于春季(63种), 但平均生物量和丰度却都是春季航次(分别为1 129.23 g/m2、707 ind/m2)明显高于秋季航次(分别为576.98 g/m2、461 ind/m2)。各断面主要优势种为疣荔枝螺、日本笠藤壶和粒屋顶螺等, 它们占总生物量和丰度的60%以上。从多样性指数来看, 洞头列岛物种多样性指数平均为1.73?0.47, 变化范围为0.83~2.10, 物种丰富度指数平均为2.26?0.33, 变化范围为1.99~2.95, 均匀度指数平均为0.62?0.19, 变化范围为0.29~0.85, 辛普森优势度指数平均为0.70?0.18, 变化范围为0.36~0.87。综合以上结果发现, 洞头列岛各断面潮间带大型底栖生物群落结构不稳定, 且物种多样性较差, 有向次生型群落结构演化的趋势, 主要原因是过度采捕、生境破碎等人为干扰过于严重导致的。     

Hawaii longline tuna fishery temporal trends in standardized catch rates and length distributions and effects on pelagic and seamount ecosystems

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基于植被丰度分析的城市植被胁迫遥感监测

以混合像元分解提取植被丰度作为主要手段,研究基于广州市区东边建成区的Hyperion高光谱遥感影像,以遥感影像预处理—特征选择—SMACC混合像元分解的步骤提取出植被丰度图,再进行PPI迭代运算纯化,提取出7种表征植被健康状况差异端元的PPI影像。经实地考察植被胁迫位置的周边人类活动的情况,结合植物生理学和光谱学分析反射率波谱曲线的变化,解释植物受到胁迫的原因,以期为城市绿地调查管理提供参考。     

Microbial responses to organic and inorganic amendments in eroded soil

The objectives of this study were to determine the changes in microbial biomass carbon, litter decomposition, microbial abundance and the soil's physical and chemical properties after poultry manure and inorganic fertilizer application in soil‐eroded areas. Four plots measuring 10 m × 10 m, located on approximately the same slope, were established in the study area. Plot 1 (P1) was an eroded plot without any treatment; Plot 2 (P2) was treated with poultry manure (N:P:K ratio of 1:0.8:0·39); Plot 3 (P3) was treated with inorganic mineral fertilizer (NPK 10:10:10); and Plot 4 (P4) was an undisturbed area (no erosion occurred). The one‐time amendments used in this study significantly increased the soil's water‐holding capacity, pH, and the total carbon and nitrogen content, but soil moisture content was not influenced by any amendment. The biomass carbon was increased 3·2‐ and 2·9‐times by the poultry manure and the NPK fertilizer amendments respectively, but the values did not reach the same level as the undisturbed area. The Gram‐positive and Gram‐negative bacteria, fungi, actinomycetes, cellulase‐producers and amylase‐producers responded positively to the additives, which was shown by an abrupt increase in their abundance. Microbial biomass carbon and abundance were shown to be closely correlated with the soil's carbon and nitrogen content. None of the amendments, on the other hand, affected the rate of litter decomposition. Copyright © 2006 John Wiley & Sons, Ltd.     

Fish assemblage structure and aquatic pollution in a Brazilian stream: some limitations of diversity indices and models for environmental impact studies

Abstract –  The aim of this study was to describe and quantify the effect of aquatic pollution on the fish assemblage structure of the Corumbataí River (Brazil), by comparing two sites with different water quality characteristics. The results revealed that abundance of individuals was low at the polluted site (B). However, the two sites did not differ significantly in species richness (total and average). This fact contradicts theories stating that portions where the transverse area of the channel is larger should present a higher biological richness. It was also observed that the ichthyofauna of site B had higher evenness, and, consequently, a tendency to a higher diversity than that at site A. This demonstrates that diversity estimates should be used cautiously in environmental impact studies, as they do not necessarily indicate better conditions of communities living in more preserved environments.     

杭州植物园野生维管植物调查

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Applying a variable-shape spatial filter to map relative abundance of manatees (Trichechus manatus latirostris)

Presented is a modified spatial filter, called a variable-shape filter, that was used to transform a map of point locations of Florida manatees (Trichechus manatus latirostris) to a contoured surface illustrating relative abundance. Rather than having a fixed polygon shape and size as conventional filters do, this method preserves constant filter area but conforms polygon shape to include only the desired land-cover categories–in this study, water. Variable-shape filter polygons are formed by starting with the cell that the point is located in and then adding the nearest contiguous cells of the desired land-cover category to the polygon until the area requirement is reached. Surfaces generated using the variable-shape filter were compared to those created with a conventional, circular, fixed-shape filter. Four filter sizes, based on an analysis of manatee hourly travel rates estimated from satellite and radio telemetry data, were used. Filter sizes, defined in terms of a circle's radius, were 125 m, which was the 25th percentile of the cumulative manatee travel-rate distribution; 325 m, the 50th percentile; 800 m, the 75th percentile; and 3,950 m, the 99th percentile. The fixed-shape and variable-shape filters differed principally in how their results were influenced by land. The variable-shape filter, programmed to maintain constant area, estimated animals to occur farther from shore than the fixed-shape filter did. Fixed-shape filter polygons were occasionally divided by land barriers, such as peninsulas, resulting in calculations of relative abundance estimates that were near the visual sighting in terms of euclidian distance but far in terms of manatee travel. The variable-shape filter was preferable primarily because it was more sensitive to manatee ecology: only cells contiguous to the animal's mapped location were included in the filter calculations.     

长期施用不同有机肥对甘薯产量和土壤生物性状的影响

以花生—甘薯轮作的长期定位试验为研究对象,研究不同(类)有机肥对甘薯产量、土壤微生物丰度和酶活性的影响,为选取合适的有机肥在提高作物产量和改善土壤生物性状方面提供依据。共选取5个施肥处理:(1)CK,空白对照;(2)NPK,单施化肥;(3)NPK+SR,化肥+稻草;(4)NPK+M,化肥+商品有机肥;(5)NPK+P,化肥+猪粪。结果表明:与CK相比,NPK、NPK+SR、NPK+M和NPK+P处理均显著增加鲜薯产量和地上部生物量(P<0.05),其中NPK+P处理效果最好。与CK比较,NPK处理显著降低土壤细菌、真菌、固氮菌和活化有机磷微生物的丰度(P<0.05),而NPK+SR、NPK+M和NPK+P处理在不同程度上缓解了NPK处理对土壤微生物丰度的抑制作用。土壤酶的加权平均值(GMea)在一定程度上可用来评价土壤酶的总体活性。与CK相比,NPK、NPK+SR和NPK+M处理的土壤酶活性显著降低(P<0.05),而NPK+P处理的土壤酶活性有所提高;对于土壤单一酶活性,NPK+P处理与CK比较显著降低土壤脲酶活性(P<0.05),但显著提高酸性磷酸酶、碱性磷酸酶和过氧化氢酶活性。此外,主成分和相关性分析表明,土壤养分和土壤有机碳与鲜薯产量和地上部生物量显著正相关,土壤pH是驱动土壤微生物丰度和土壤酶活性变化的主要因素。因此,长期有机无机肥配施通过提高土壤养分、有机碳含量以及调节土壤pH变化在提高甘薯产量和改善土壤生物性状方面取得良好效果。总体来说,化肥配施猪粪在培肥地力和增产增收方面效果最佳。