四川省制浆造纸行业可持续发展建议

造纸业是与民生关联度极高的行业.为改变国内造纸行业污染局面、整合企业规模、合理原料结构、提高技术装备、改革落后生产工艺,国家先后出台了多项政策规定.特别是2008年新的<制浆造纸工业水污染物排放标准>(GB3544)颁布后,四川省制浆造纸行业面临巨大的整改压力.如何抓住产业调整机遇,加快产品结构调整和生产方式转变,努力...     

名山旅游区旅游环境容量动态变化规律研究——以张家界森林公园为例

在研究名山旅游区资源生态系统特点及环境管理现状的基础上,以张家界森林公园为例,对名山旅游区旅游环境容量的各要素伴随名山旅游区旅游业发展所显现的动态变化状况进行研究,探讨其变化规律,为制定合理环境管理容量与环境管理措施提供依据.     

煤矿安全文化对员工行为安全影响作用的实证研究

通过将煤矿安全文化看作由安全目标、安全承诺、安全规程、安全激励、安全培训和安全沟通这6个要素构成,利用3个矿业集团289份矿工的问卷调查数据,运用结构方程模型(SEM)方法,实证研究了煤矿安全文化对员工行为安全的影响作用。研究表明:煤矿安全文化通过员工安全能力和安全动机对员工的安全服从行为和安全参与行为具有显著的影响作用,然而不同安全文化要素的影响途径和影响作用是不同的;员工安全能力和安全动机对员工的服从行为和参与行为都具有直接的正向影响作用;安全激励对员工安全服从行为、安全沟通对员工参与行为存在直接正向影响作用。     

近17年鄱阳湖区景观格局动态变化研究

通过对1989、1999和2006年3期遥感影像进行解译,借助ARCGIS、FRAGSTATS等软件对鄱阳湖区近17年景观格局动态变化进行分析。结果表明：近17年湖区景观空间结构在自然因素和人类活动的影响下发生显著变化。从景观水平上看,湖区整体景观的破碎化程度不断增大,各斑块类型在空间上的分布趋于均匀和分散,景观中斑块的形状渐趋不规则,复杂程度加大。在斑块类型水平上,研究区水体的破碎化程度增加,斑块向着小型化方向发展,斑块之间的结合度降低,形状逐渐变得复杂,水体斑块之间的水力联系减弱;草地和林地的空间结构相对稳定,变化并不显著;耕地虽然是研究区的优势景观类型,但在近17年间,其优势地位被逐渐削弱,破碎化程度也在逐渐加大,斑块形状的规则性降低,各斑块之间的分离性加大;滩地的变化主要受水文情势和泥沙淤积的影响,破碎化程度经历了先加大、后降低的过程,最大斑块面积有所增大;建设用地的变化最为明显,其破碎化程度也有所加大,但斑块间的连接程度相对研究初期有所增加;未利用地是研究区面积最小的景观类型,其景观破碎化程度则有所降低,斑块形状也渐趋简单。     

Indirect effects of African megaherbivore conservation on bat diversity in the world's oldest desert

In extreme environments, temperature and precipitation are often the main forces responsible for structuring ecological communities and species distributions. The role of biotic interactions is typically thought to be minimal. By clustering around rare and isolated features, like surface water, however, effects of herbivory by desert-dwelling wildlife can be amplified. Understanding how species interact in these environments is critical to safeguarding vulnerable or data-deficient species. We examined whether African elephants (Loxodonta africana), black rhinoceros (Diceros bicornis), and southern giraffe (Giraffa giraffa) modulate insectivorous bat communities around permanent waterholes in the Namib Desert. We estimated megaherbivore use of sites based on dung transects, summarized vegetation productivity from satellite measurements of the normalized difference vegetation index, and surveyed local bat communities acoustically. We used structural equation models to identify relationships among megaherbivores and bat species richness and dry- (November 2016–January 2017) and wet- (February–May 2017) season bat activity. Site-level megaherbivore use in the dry season was positively associated with bat activity—particularly that of open-air foragers—and species richness through indirect pathways. When resources were more abundant (wet season), however, these relationships were weakened. Our results indicate that biotic interactions contribute to species distributions in desert areas and suggest the conservation of megaherbivores in this ecosystem may indirectly benefit insectivorous bat abundance and diversity. Given that how misunderstood and understudied most bats are relative to other mammals, such findings suggest that managers pursue short-term solutions (e.g., community game guard programs, water-point protection near human settlements, and ecotourism) to indirectly promote bat conservation and that research includes megaherbivores’ effects on biodiversity at other trophic levels.     

影响振动环境试验的若干关键技术要点解析

从振动试验方案设计、试验方法和步骤、试验设备选择、振动试验控制方法等几个方面对影响振动试验的关键技术进行了详细的解析;并结合结构动力学阐述了振动试验夹具设计的注意要点。     

Effects of acidification on aquatic ecosystems

Effects of acidification on aquatic ecosystems are analyzed on the basis of an analytical synopsis of relevant data. Major active agents influencing aquatic organisms and main trends in the reorganization of microbial, phyto- and zooplanktonic, benthic, and fish communities in an acidified environment are described. A generalized concept of changes in ecosystems caused by acid precipitation and accompanying factors is formulated. These changes include the reduction of biodiversity of all structural elements due to the disappearance of species sensitive to acidification, modification of trophic structure, and decrease of fish stock.Translated from Ekologiya, No. 2, 2005, pp. 110–119.Original Russian Text Copyright © 2005 by Moiseenko.     

Monitoring the growth of American beech affected by beech bark disease in Maine using the Kalman filter

The effect of beech bark disease on tree growth was tracked using paired resistant and susceptible American beech trees in two locations in Maine. Within each site, the paired trees were chosen in close proximity and with similar morphological characteristics (e.g. stem diameter and crown class) to minimize environment effects in subsequent analysis. A Kalman filter approach was employed to analyse the yearly time-dependent mean differences between paired susceptible and resistant tree-ring widths using simple structural time series models in state space form. On one site, under the influence of a moderate maritime climate, stand dynamics is hypothesized to account for the 34 year difference in onset of decline of trees in codominant, versus those in the intermediate crown classes. The harsher winter conditions associated with the second, more northerly site and known to limit the insect component of the disease complex, are hypothesized to be more of a factor in the close (six year) difference in decline onset between the two crown classes on this site. Some strengths and cautions in the Kalman filter approach are discussed in relation to the analysis of time-dependent trends in tree-ring series.     

Latitudinal Gradients of Trophics in Ural Macrolepidoptera: The Role of Food Quality

The Macrolepidoptera fauna of the Urals, from the southern to the northern boundary of the forest zone (i.e., from the forest–steppe of the Southern Urals to the forest–tundra of the Polar Urals) has been analyzed. It has been demonstrated that the proportion of Lepidoptera feeding on woody plants, including evergreens, increases in this direction. Among the Heterocera, the proportion of species feeding on graminoids decreases; in the Polar Urals, none of these species is specialized. The food spectrum is particularly variable in noctuids and almost invariable in geometrids and Rhopalocera. It is assumed that foods with a low nutrient value (grasses, mosses, lichens, plant debris, wood, and roots of various plants) prevent Macrolepidoptera species from spreading in the Subarctic region. In the Polar Urals, multiyear developmental cycles and wintering at the larval stage are related to feeding on these types of food.