排序方式: 共有66条查询结果,搜索用时 453 毫秒
1.
2.
Effect of Habitat Complexity on Richness, Abundance and Distributional Pattern of Forest Birds 总被引:1,自引:1,他引:0
Structurally complex forests provide more diverse conditions in comparison to homogenous forests because of greater variety of microhabitats and trees. This study assesses the association of bird species richness, abundance, and distributional pattern with habitat complexity (HC) in Kheyrud Forest in the north of Iran. Birds were surveyed during spring 2009 by 100 point counts. In each point count six habitat features related to the index of HC were computed and scored from 0 to 3. Then the scores were summed and divided into two groups of low and high complexity, HC ≤ 6 and HC > 6, respectively. To compare bird richness and abundance in different HCs, a two sample t-test was used. Presence and absence of bird species at each plot as a dependent variable were compared with the vegetation characteristics as an independent variable by means of the Canonical Correspondence Analysis. The results revealed bird species richness and abundance were significantly higher in more complex habitats. Bird species can be divided into two groups, the first group including species which associated with late successional stages and the second group, species belonging to early successional stages. Numbers of birds belonging to the first group declined in less complex forests, whereas the numbers of birds belonging to the second group increased. At the stand scale, our results reveal that bird abundance and richness are strongly associated with the complexity of vegetation structure in the study area. 相似文献
3.
Kamarehie Bahram Jafari Ali Ghaderpoori Mansour Azimi Faramarz Faridan Mohammad Sharafi Kiomars Ahmadi Fatemeh Karami Mohammad Amin 《Environmental science and pollution research international》2020,27(30):37514-37526
Environmental Science and Pollution Research - With the rapid growth of population, development of different industries, and production of several ranges of products, the generation of municipal... 相似文献
4.
Mahdi Ahmadi Josh Minot George Allen Lisa Rector 《Journal of the Air & Waste Management Association (1995)》2020,70(4):393-409
ABSTRACTA study was undertaken to identify patterns of consumer use of outdoor wood boilers or outdoor wood furnaces (technically referred to as outdoor wood-fired hydronic heaters (OWHHs)) and indoor wood stoves (IWSs) to inform the development of performance testing protocols that reflect real-life operating conditions. These devices are manually fed, and their usage protocols are a function of a number of variables, including user habits, household characteristics, and environmental factors. In this study, researchers logged the stack wall temperatures of 4 OWHH and 20 IWS units in the states of New York and Washington over two heating seasons. Stack wall temperature is an indicator of changes in combustion modes. Two algorithms were developed to identify usage modes and cold and warm start refueling events from the stack wall temperature time series. A linear correlation analysis was conducted to evaluate the effect of heat demand on usage patterns. The results and methods presented here will inform the cataloging of typical operational patterns of OWHHs and IWSs as a step in the development of performance testing procedures that represent actual in-home usage patterns.Implications: Current US regulatory programs for residential wood heating use a certification program to assess emissions and efficiency performance. Testing under this program uses a test that burns 100% of a single, standardized wood fuel charge to assess performance at different steady-state load conditions. This study assessed in-field operational patterns to determine if the current certification approach accurately characterized typical homeowner use patterns. The data from this study can be used to inform revisions to testing methods to increase certification test comparability between lab and field performance. 相似文献
5.
A novel spectrophotometric method for the determination of molybdenum(VI) by using a natural reagent, water extract of slippery elm tree leaves, is developed. Molybdenum(VI) reacts with this natural reagent to form an orange colored product. The formed product shows maximum absorbance at 418 nm with a molar absorptivity value of 0.57 × 104 L mol?1 cm?1, and this method is linear in the 0.4–10 mg L?1 concentration range. The detection limit value was found to be 0.0350 mg L?1. The proposed method is simple, clean, low cost, selective, and sensitive. It was applied to the analytic samples with satisfactory results. 相似文献
6.
Seyed Taleb Hosseini Vahid Chegini Masoud Sadrinasab Seyed Mostafa Siadatmousavi 《Journal of Coastal Conservation》2018,22(6):1093-1106
The spatio-temporal variability of temperature and salinity was studied for a creek network and its adjacent coastal waters along the northwestern coast of the Persian Gulf during warm and cold months. Salinity variations and tidal fluctuations were found to be out of phase throughout the creek. Temperature variations at the creek were exhibit a direct correlation with tidal fluctuations during cold months and were inversely related during warm months. The creek water was colder (warmer) than offshore water during the cold (warm) season. The salinity values observed inside this inverse estuary were higher during the warm season than the corresponding values during the cold season due to a change in evaporation rates; while the open water salinity had an opposite pattern. Using salinity as a tracer, the water-age (WA) was calculated, which shows almost linear increase from the mouth to the head. The maximum WA increases from ~10 days in winter to ~30 days in summer due to the corresponding increase in longitudinal salinity gradient. Based on the calculated non-dimensional Peclet number, the diffusion process is more rapid than the advection process in this water body, especially during the cold season. 相似文献
7.
Umar Ibrahim Khalil Nourani Vahid Gökçekuş Hüseyin 《Environmental science and pollution research international》2021,28(36):49663-49677
Environmental Science and Pollution Research - Accuracy in the prediction of the particulate matter (PM2.5 and PM10) concentration in the atmosphere is essential for both its monitoring and... 相似文献
8.
Ahmadi Mohsen Sharifi Abbas Khalili Sarv 《Environmental science and pollution research international》2021,28(12):14521-14529
Environmental Science and Pollution Research - The COVID-19 pandemic is one of the contagious diseases involving all the world in 2019–2020. Also, all people are concerned about the future of... 相似文献
9.
Soleymanfar Vahid Reza Makui Ahmad Taleizadeh Ata Allah Tavakkoli-Moghaddam Reza 《Environment, Development and Sustainability》2022,24(4):5317-5343
Environment, Development and Sustainability - In this work, a new model is developed to determine optimum sustainable economic order quantity (EOQ) and economic production quantity (EPQ) values for... 相似文献
10.