Polymorphic mountain whitefish (Prosopium williamsoni) in a coastal riverscape: size class assemblages,distribution, and habitat associations

We compared the assemblage structure, spatial distributions, and habitat associations of mountain whitefish (Prosopium williamsoni) morphotypes and size classes. We hypothesised that morphotypes would have different spatial distributions and would be associated with different habitat features based on feeding behaviour and diet. Spatially continuous sampling was conducted over a broad extent (29 km) in the Calawah River, WA (USA). Whitefish were enumerated via snorkelling in three size classes: small (10–29 cm), medium (30–49 cm), and large (≥50 cm). We identified morphotypes based on head and snout morphology: a pinocchio form that had an elongated snout and a normal form with a blunted snout. Large size classes of both morphotypes were distributed downstream of small and medium size classes, and normal whitefish were distributed downstream of pinocchio whitefish. Ordination of whitefish assemblages with nonmetric multidimensional scaling revealed that normal whitefish size classes were associated with higher gradient and depth, whereas pinocchio whitefish size classes were positively associated with pool area, distance upstream, and depth. Reach‐scale generalised additive models indicated that normal whitefish relative density was associated with larger substrate size in downstream reaches (R² = 0.64), and pinocchio whitefish were associated with greater stream depth in the reaches farther upstream (R² = 0.87). These results suggest broad‐scale spatial segregation (1–10 km), particularly between larger and more phenotypically extreme individuals. These results provide the first perspective on spatial distributions and habitat relationships of polymorphic mountain whitefish.     

万亩果园湿地一期示范区升级工程景观特点与主要 施工技术

介绍万亩果园湿地一期示范区升级工程湿地景观的特点及其施工创新技术。该工程因地制宜，从实际出发，制定切实可行的施工方案。重点介绍改善水质方面采用的3个先进的施工技术——引进新型的材料、合理选用水生植物、调控生态系统，使水体长期保持洁净，终年不需要换水，达到预期的效果。     

有机化学平台课程的构建与思考

通过合理把握有机化学课程知识体系和教学层次,将知识体系模块化,内容层次多元化,同时把课程设计与各个专业培养目标有机融合,建设有机化学平台课程并进一步完善评价制度,从而实现平台课程服务人才培养的目标.     

基于PSO-BP神经网络的外贸发展状况的评价

以我国对外贸易的实际情况为基础，建立了评价外贸发展状况的一套指标体系.使用主成分分析方法对所有评价指标进行预处理之后，借助粒子群优化算法改进了BP神经网络算法，构建了外贸发展状况的评价模型.评价模型在具体应用中，评价结果较为准确，具有一定的科学性和合理性.     

中外刺绣艺术特色资源库建设

刺绣工艺是传统的装饰工艺，介绍了中外刺绣艺术特色资源库建设的选题背景和定位，从内容结构、技术标准、资源建设及项目的组织和管理四个方面阐述了中外刺绣艺术特色资源库的建设经验。     

Aggregate-related changes in network patterns of nematodes and ammonia oxidizers in an acidic soil

Nitrification plays a central role in global nitrogen cycle, which is affected by biological interaction between soil microfauna and microorganisms. However, the complexity of soil biotic communities made it difficult to reveal organizational principles of the community and the interactions among species. Here, we used the network analysis to decipher the interactions between nematodes and ammonia oxidizers within aggregate fractions under 10-year manure application, and examine their associations with soil variables and potential nitrification activity (PNA). Three aggregate fractions included large macroaggregates (>2000 μm, LA), small macroaggregates (250–2000 μm, SA), and inter-aggregate soil and space (<250 μm, IA). Aggregate factions showed a remarkable effect on association networks of nematodes and ammonia oxidizers. The average connectivity (avgK) and the number of edges in overall networks increased with increasing aggregate sizes, while the average geodesic distance (GD) followed the opposite trend. The LA network could be viewed as a better organized or a better operational soil food web with more functional interrelated members than the SA and IA networks. The modules related to PNA were significantly correlated and clustered together as meta-modules in networks of aggregate fractions. The role-shifts prevailed among the network members such as significant module memberships (MMs) and generalist/specialist operational taxonomic units (OTUs). A half of shared nodes were further identified as shared MMs, dominated by ammonia-oxidizing bacteria (AOB) especially for Nitrosospira cluster 3a and 10. Soil pH could explain partly the shift of module hubs in different networks, while grazing by bacterivores might account for three exclusively connecters related to Nitrososphaera clusters 1.1. The strongly coupled modules correlated positively to pH and total carbon (TC), regardless of aggregate fractions. The network analysis approach provided new insights into potential importance of network interactions between nematodes and ammonia oxidizers in soil nitrogen cycling.     

阿克苏地区经济发展与建设用地集约利用耦合研究

以阿克苏地区的经济发展与建设用地集约利用的两个子系统为研究对象,基于二者与社会协同理论,同时运用熵值法、统计分析、系统评价和耦合模型等方法对其进行研究。建立阿克苏地区经济发展与建设用地耦合模型,然后对耦合关系进行探讨,揭示经济发展与建设用地集约利用的关系。研究结果表明,阿克苏地区经济发展和建设用地集约利用水平都较低;经济发展—建设用地集约利用系统中两子系统在反正切函数模型中的协调性越来越差;两子系统在经济和建设用地集约利用水平较低时高度耦合,阿克苏地区的经济水平较建设用地集约利用水平快速发展,建设用地集约水平急需改善。     

大别山区域生态农业建设基本指标及实践研究——以湖北省黄冈市为例

以黄冈市为例,分析了大别山区域生态农业建设的基本指标要求,以及落实大别山区域生态农业建设基本指标必须采取的具体措施.     

网络时代高校图书馆信息资源建设研究

信息技术给高校图书馆的发展带来了机遇和挑战,信息资源已经成为高校图书馆馆藏资源的重要组成部分。从理论、观念、服务模式等方面阐述了信息时代高校图书馆信息资源建设应采取的措施。     

市政工程中给排水施工的管理分析

随着国内城市化的推进，市政工程的给排水工程越发显得重要。传统的给排水施工技术已经无法满足城市发展要求，社会对给排水的施工质量提出了更高地要求。文章结合当前给排水施工管理现状，对给排水施工的施工管理各方面进行简要探析。