全文获取类型
收费全文 | 72篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 1篇 |
废物处理 | 2篇 |
环保管理 | 5篇 |
综合类 | 2篇 |
基础理论 | 16篇 |
污染及防治 | 34篇 |
评价与监测 | 4篇 |
社会与环境 | 9篇 |
出版年
2022年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 6篇 |
2012年 | 3篇 |
2011年 | 7篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 6篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
排序方式: 共有73条查询结果,搜索用时 15 毫秒
71.
Urbanization decreases species diversity, but it increases the abundance of certain species with high tolerance to human activities.
The safe-habitat hypothesis explains this pattern through a decrease in the abundance of native predators, which reduces predation
risk in urban habitats. However, this hypothesis does not consider the potential negative effects of human-associated disturbance
(e.g., pedestrians, dogs, cats). Our goal was to assess the degree of perceived predation risk in house finches (Carpodacus mexicanus) through field studies and semi-natural experiments in areas with different levels of urbanization using multiple indicators
of risk (flock size, flight initiation distance, vigilance, and foraging behavior). Field studies showed that house finches
in more urbanized habitats had a greater tendency to flock with an increase in population density and flushed at larger distances
than in less urbanized habitats. In the semi-natural experiment, we found that individuals spent a greater proportion of time
in the refuge patch and increased the instantaneous pecking rate in the more urbanized habitat with pedestrians probably to
compensate for the lower amount of foraging time. Vigilance parameters were influenced in different ways depending on habitat
type and distance to flock mates. Our results suggest that house finches may perceive highly urbanized habitats as more dangerous,
despite the lower number of native predators. This could be due to the presence of human activities, which could increase
risk or modify the ability to detect predators. House finches seem to adapt to the urban environment through different behavioral
strategies that minimize risk. 相似文献
72.
Five different fractions of the biodegradable municipal solid waste (BMSW) were evaluated as potential animal feedstuffs. For each source of waste (meat waste (MW), fish waste (FW), fruit and vegetables waste (FVW), restaurant waste (RW), household waste (HW)), samples were obtained from small shops (butchers, fishmongers, fruit and vegetable shops), restaurants and a MSW treatment plant (household waste). The chemical composition, microbiological characterization, dioxins, furans, PCB's and mineral content were determined for every type of waste fraction. The analysed biodegradable waste presented high moisture content (from 60% to 90%). Some fractions were dense in one nutrient: meat waste in ether extract, fish waste in crude protein, fruit and vegetable waste in nitrogen free extract. The other studied fractions (restaurant fraction and household fraction) presented a more balanced composition, but the presence of toxic concentrations of contaminants such as metals was higher than European legislation permitted values in animal feeding. From a microbiological standpoint, a heat treatment at 65 degrees C for 20 min was sufficient to ensure microbiological quality of the samples. This treatment was also advisable to reduce the moisture content: a lower moisture content facilitates the waste handling and processing and, therefore, the inclusion of these waste fractions in commercial animal diets. This paper presents a potential alternative for the recovery of organic matter content in municipal solid waste. The results obtained in this research and the feedstuffs legislation in force related to animal feed, indicated that some of the studied biodegradable waste fractions (meat waste, fruit and vegetable waste and fish waste) could be considered as alternatives to typical raw materials used in animal feeds. 相似文献
73.
Rolón Eugenia Rosso Juan José Mabragaña Ezequiel Tripodi Pamela Bavio Marta Bidone Camila Volpedo Alejandra V. Avigliano Esteban 《Environmental science and pollution research international》2022,29(39):58843-58868
Environmental Science and Pollution Research - Environmental pollution affects the quality of the natural environment where major and trace elements have been commonly found to accumulate in biotic... 相似文献