The fallacy of the missing middle: physics →…→ fisheries

In this paper I discuss some of the shortcomings of today's marine science in response to a recently published paper by Ann Gargett (1997). Three problem areas have been identified in the field linking climate forcing and fish production: First, the yet-to-be established observational proof for a relationship between the two; Second, the strongly neglected biology of organisms at evolutionary and ecological time scales; and thrird, the disregard for spatial and temporal scales in the discussion of mechanisms and supporting data.     

Predicting Carbon Stocks Following Reforestation of Pastures: A Sampling Scenario‐Based Approach for Testing the Utility of Field‐Measured and Remotely Derived Variables

Reforestation of agricultural lands is an important means of restoring land and sequestering carbon (C). At large scales, the labour and costs of direct measurement of ecosystem responses can be prohibitive, making the development of models valuable. Here, we develop a new sampling scenario‐based modelling approach coupled with Bayesian model averaging to build predictive models for absolute values in mixed‐species woody plantings and differences from their adjacent pasture, for litter stocks, soil C stocks and soil C:N ratios. Modelling scenarios of increasing data availability and effort were tested. These included variables that could be derived without a site visit (e.g. location, climate and management) that were sampled in the adjacent pasture (e.g. soil C and nutrients) or were sampled in the environmental planting (e.g. vegetation, litter properties, soil C and nutrients). The predictive power of models varied considerably among C variables (litter stocks, soil C stocks and soil C:N ratios in tree plantings and their differences to their adjacent pastures) and the model scenarios used. The use of a sampling scenario‐based approach to building predictive models shows promise for monitoring changes in tree plantings, following reforestation. The approach could also be readily adapted to other contexts where sampling effort for predictor variables in models is a major potential limitation to model utilization. This study demonstrates the benefit of exploring scenarios of data availability during modelling and will be especially valuable where the sampling effort differs greatly among variables. Copyright © 2016 John Wiley & Sons, Ltd.     

生态学理论在城市园林绿化中的应用研究

本文从人与自然和谐共处、可持续发展的角度出发，以生态学理论框架为依托，系统地总结了在城市园林建设中生态学理念的渗透及运用，为城市生态园林设计提供了理论指导和设计参考，同时得出我国生态园林的下一步工作重点要放在恢复生态学的应用上，并且要实现现代城市生态园林的建设要多学科、多角度共同协作的结论。     

多基因型大豆的生理生态研究

[目的]为大豆的高产生理生态提供依据。[方法]在大豆高产田选用单基因型大豆鲁豆13、日选、黄沙、科丰6号、92-8,并等量混合种植组成包括6个双基因型大豆的11个处理,研究多基因型大豆的生理生态。[结果]双基因型群体日选+科丰6号的产量最高,比单基因型增产18.6%~44.7%。极值出现在日选+科丰6号中的生理指标有茎粗、分枝、叶数、中部叶重、上部叶重(第2峰值)、叶面积指数(第2峰值),与产量关系较为密切,但没达显著水平。高产双基因型的指标几乎均超出或接近单基因型高值,茎粗、分枝、叶面积系数、干物质积累、中上部叶重、产量有明显优势,产量较低的双基因型相反。盛花期中上部截留96.0%~97.0%、漏光损失1.0%~2.5%较为适宜;鼓粒期中上部截留65.0%~75.0%较为适宜,到达地面的光不宜超过10.0%。[结论]基因型搭配较单基因型增产显著,增产幅度达8.7%~44.7%,叶面积系数、干物质积累量、中上部叶重明显提高,以尖叶品种与阔叶品种搭配较为合理。     

信息生态管理技术研究

为了更好地实现信息生态的平衡,探讨了几种可用于信息生态管理的技术,阐述了几种信息生态管理技术的结构特点及开发过程等。     

沈阳市河流生态建设项目实施建议

近年来,因干旱少雨等自然灾害影响及人类生产活动对环境的破坏,致使一些中小河流生态功能遭到不同程度的破坏。结合沈阳市近年来河流生态建设的实施情况,从工程措施和生物措施两方面详细介绍了针对不同河流状况的生态建设措施,对今后类似工程建设提供借鉴。     

黑龙江省灌木林资源发展存在的问题及对策

根据黑龙江省森林资源现状和灌木林的分布特点，提出了我省灌木林经营存在的问题和今后发展对策。     

在生态可持续背景下对建筑用木材的再认识

透过生态、可持续发展的视野,对建筑用木材在生态性、高效性及可持续运用等方面进行剖析,力图破除当前对木材在建筑中使用的片面认识,唤起建筑界、林业界对木材在当代建筑中大量使用的新的思考和探索。     

Multi-scale use of lands providing anthropogenic resources by American Crows in an urbanizing landscape

The conversion of forests and farmlands to human settlements has negative impacts on many native species, but also provides resources that some species are able to exploit. American Crows (Corvus brachyrhynchos), one such exploiter, create concern due to their impact as nest predators, disease hosts, and cultural harbingers of evil. We used various measures of crow abundance and resource use to determine crows’ response to features of anthropogenic landscapes in the Puget Sound region of the United States. We examined land cover and land use composition at three spatial scales: study sites (up to 208 ha), crow home ranges within sites (18.1 ha), and local land cover (400 m²). At the study site and within-site scales crow abundance was strongly correlated with land cover providing anthropogenic resources. In particular, crows were associated with the amount of ‘maintained forest’ cover, and were more likely to use grass and shrub cover than forest or bare soil cover. Although crows did not show a generalized response to an edge variable, they exhibited greater use of patchy habitat created by human settlements than of native forests. Radio-tagged territorial adults used resources within their home ranges relatively evenly, suggesting resource selection had occurred at a larger spatial scale. The land conversion pattern of new suburban and exurban settlements creates the mix of impervious surfaces and maintained vegetation that crows use, and in our study area crow populations are expected to continue to increase. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Performance of Agricultural Systems under Contrasting Growing Season Conditions in South-western Quebec

Climate change will alter temperature and rainfall patterns over North American agricultural regions and there will be a need to adapt crop production systems to the altered conditions. A set of field experiments were conducted in south-western Quebec, Canada, with soybean ( Glycine max L.), corn ( Zea mays L.), sorghum ( Sorghum bicolor L.) × sudangrass ( Sorghum sudanense Piper) hybrid and switchgrass ( Panicum virgatum L.) under two tillage and three nitrogen fertility regimes, to study their performance in three successive growing seasons (2001–2003), two of them with unusually warm and dry conditions. The annual crops were established in two tillage systems: conventional and no-till (NT). All crops except soybean were fertilized with three levels of nitrogen: corn – 0, 90 and 180 kg N ha⁻¹, sorghum-sudangrass – 0, 75 and 150 kg N ha⁻¹, switchgrass – 0, 30 and 60 kg N ha⁻¹. The 2001 and 2002 seasons were hotter and drier than the 2003 season, which was the most favourable for crop growth. The capacity of the crops to yield in dry seasons was as follow: switchgrass > sorghum-sudangrass > corn > soybean. The corn and sorghum-sudangrass responses to nitrogen fertilizer were low in 2001 due to the combined effect of dry growing season and coarse soil texture. Soybean did not perform well under NT. Corn yielded better at the highest nitrogen fertilizer rate under NT when the early season was warmer than the normal. Our results show that switchgrass and sorghum-sudangrass could be an option in south-western Quebec if the frequency of hot and dry seasons increase in the future, because of climate change.