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601.
602.
P. H. Patterson A. Adrizal R. M. Hulet R. M. Bates C. A.B. Myers G. P. Martin 《Journal of environmental science and health. Part. B》2013,48(2):199-204
This study sought to evaluate the potential of trees planted around commercial poultry farms to trap ammonia (NH3), the gas of greatest environmental concern to the poultry industry. Four plant species (Norway spruce, Spike hybrid poplar, Streamco willow, and hybrid willow) were planted on eight commercial farms from 2003 to 2004. Because temperature (T) can be a stressor for trees, T was monitored in 2005 with data loggers among the trees in front of the exhaust fans (11.4 to 17.7 m) and at a control distance away from the fans (48 m) during all four seasons in Pennsylvania. Norway spruce (Picea abies) foliage samples were taken in August 2005 from one turkey and two layer farms for dry matter (DM) and nitrogen (N) analysis. The two layer farms had both Norway spruce and Spike hybrid poplar (Populus deltoides × Populus nigra) plantings sampled as well allowing comparisons of species and the effect of plant location near the fans versus a control distance away. Proximity to the fans had a clear effect on spruce foliar N with greater concentrations downwind of the fans than at control distances (3.03 vs. 1.88%; P ≤ 0.0005). Plant location was again a significant factor for foliar N of both poplar and spruce on the two farms with both species showing greater N adjacent to the fans compared to the controls (3.75 vs. 2.32%; P ≤ 0.0001). Pooled foliar DM of both plants was also greater among those near the fans (56.17, fan vs. 44.67%, control; P ≤ 0.005). Species differences were also significant showing the potential of poplar to retain greater foliar N than spruce (3.52 vs. 2.55%; P ≤ 0.001) with less DM (46.00 vs. 54.83%; P ≤ 0.05) in a vegetative buffer setting. The results indicated plants were not stressed by the T near exhaust fans with mean seasonal T (13.04 vs. 13.03°C, respectively) not significantly different from controls. This suggested poultry house exhaust air among the trees near the fans would not result in dormancy stressors on the plants compared to controls away from the fans. 相似文献
603.
A. Adrizal P. H. Patterson R. M. Hulet R. M. Bates C. A.B. Myers G. P. Martin 《Journal of environmental science and health. Part. B》2013,48(1):96-103
This study evaluated the potential of trees planted around commercial poultry farms to trap ammonia (NH3) and dust or particulate matter (PM). Norway spruce, Spike hybrid poplar, hybrid willow, and Streamco purpleosier willow were planted on five commercial farms from 2003 to 2004. Plant foliage was sampled in front of the exhaust fans and at a control distance away from the fans on one turkey, two laying hen, and two broiler chicken farms between June and July 2006. Samples were analyzed for dry matter (DM), nitrogen (N), and PM content. In addition, NH3 concentrations were measured downwind of the exhaust fans among the trees and at a control distance using NH3 passive dosi–tubes. Foliage samples were taken and analyzed separately based on plant species. The two layer farms had both spruce and poplar plantings whereas the two broiler farms had hybrid willow and Streamco willow plantings which allowed sampling and species comparisons with the effect of plant location (control vs. fan). The results showed that NH3 concentration h? 1 was reduced by distance from housing fans (P ≤ 0.0001), especially between 0 m (12.01 ppm), 11.4 m (2.59 ppm), 15 m (2.03 ppm), and 30 m (0.31 ppm). Foliar N of plants near the fans was greater than those sampled away from the fans for poplar (3.87 vs. 2.56%; P ≤ 0.0005) and hybrid willow (3.41 vs. 3.02%; P ≤ 0.05). The trends for foliar N in spruce (1.91 vs. 1.77%; P = 0.26) and Streamco willow (3.85 vs. 3.33; P = 0.07) were not significant. Pooling results of the four plant species indicated greater N concentration from foliage sampled near the fans than of that away from the fans (3.27 vs. 2.67%; P ≤ 0.0001). Foliar DM concentration was not affected by plant location, and when pooled the foliar DM of the four plant species near the fans was 51.3% in comparison with 48.5% at a control distance. There was a significant effect of plant location on foliar N and DM on the two layer farms with greater N and DM adjacent to fans than at a control distance (2.95 vs. 2.15% N and 45.4 vs. 38.2% DM, respectively). There were also significant plant species effects on foliar N and DM with poplar retaining greater N (3.22 vs. 1.88%) and DM (43.7 vs. 39.9%) than spruce. The interaction of location by species (P ≤ 0.005) indicated that poplar was more responsive in terms of foliar N, but less responsive for DM than spruce. The effect of location and species on foliar N and DM were not clear among the two willow species on the broiler farms. Plant location had no effect on plant foliar PM weight, but plant species significantly influenced the ability of the plant foliage to trap PM with spruce and hybrid willow showing greater potential than poplar and Streamco willow for PM2.5(0.0054, 0.0054, 0.0005, and 0.0016 mg cm? 2; P ≤ 0.05) and total PM (0.0309, 0.0102, 0.0038, and 0.0046 mg cm? 2, respectively; P ≤ 0.001). Spruce trapped more dust compared to the other three species (hybrid willow, poplar, and Streamco willow) for PM10 (0.0248 vs. 0.0036 mg cm? 2; P ≤ 0.0001) and PM> 10 (0.0033 vs. 0.0003 mg cm? 2; P = 0.052). This study indicates that poplar, hybrid willow, and Streamco willow are appropriate species to absorb poultry house aerial NH3–N, whereas spruce and hybrid willow are effective traps for dust and its associated odors. 相似文献
604.
通过对国内典型铬渣处理的项目进行分析,并结合某铬渣污染治理工程实例,从反应机理、解毒工艺、工艺适应性、资源回收利用、设备选型、处理规模、场址选择、污染控制及安全生产和经济性方面对铬渣湿法解毒和干法解毒技术在实际应用中的选择进行对比,为该项目提出了更适合的解毒技术。 相似文献
605.
606.
本文综述了20多年来汞在土壤-大气界面间交换的研究现状,包括汞在大气和土壤中的存在形态、大气汞的干湿沉降、土壤汞释放及影响因素的研究,分析其存在的问题,并提出了未来的研究重点。 相似文献
607.
608.
Daniel Kozák Marek Svitok Veronika Zemlerová Martin Mikoláš Thibault Lachat Laurent Larrieu Yoan Paillet Arne Buechling Radek Bače William S. Keeton Lucie Vítková Krešimir Begovič Vojtěch Čada Martin Dušátko Matej Ferenčík Michal Frankovič Rhiannon Gloor Jeňýk Hofmeister Pavel Janda Ondrej Kameniar Tomáš Kníř Linda Majdanová Marek Mejstřík Jakob Pavlin Dheeraj Ralhan Ruffy Rodrigo Catalin-Constantin Roibu Michal Synek Ondřej Vostarek Miroslav Svoboda 《Conservation biology》2023,37(3):e14066
Protecting structural features, such as tree-related microhabitats (TreMs), is a cost-effective tool crucial for biodiversity conservation applicable to large forested landscapes. Although the development of TreMs is influenced by tree diameter, species, and vitality, the relationships between tree age and TreM profile remain poorly understood. Using a tree-ring-based approach and a large data set of 8038 trees, we modeled the effects of tree age, diameter, and site characteristics on TreM richness and occurrence across some of the most intact primary temperate forests in Europe, including mixed beech and spruce forests. We observed an overall increase in TreM richness on old and large trees in both forest types. The occurrence of specific TreM groups was variably related to tree age and diameter, but some TreM groups (e.g., epiphytes) had a stronger positive relationship with tree species and elevation. Although many TreM groups were positively associated with tree age and diameter, only two TreM groups in spruce stands reacted exclusively to tree age (insect galleries and exposed sapwood) without responding to diameter. Thus, the retention of trees for conservation purposes based on tree diameter appears to be a generally feasible approach with a rather low risk of underrepresentation of TreMs. Because greater tree age and diameter positively affected TreM development, placing a greater emphasis on conserving large trees and allowing them to reach older ages, for example, through the establishment of conservation reserves, would better maintain the continuity of TreM resource and associated biodiversity. However, this approach may be difficult due to the widespread intensification of forest management and global climate change. 相似文献
609.
Verónica Reyes-Galindo Juan Pablo Jaramillo-Correa Karina Carrasco Nava Alejandra Elizabeth De-la-Rosa-González David Flores Flores Mauricio Martínez Luis Alberto Monroy-De-la-Rosa Miguel Ángel Morelos Zamora Billy Emmanuel Ramírez Morales Oliver Tanui Ramírez Morales María del Pilar Rodríguez Maurilio Salazar Zamora Claudio Zamora Callejas Rafael Zamora Callejas César Zamora Tonatiuh Zamora Victor Alejandro González-Camacho Erick Rebollo Ricardo Torres-Jardón Ana Wegier Alicia Mastretta-Yanes 《Conservation biology》2023,37(5):e14112
Peri-urban forest monitoring requires indicators of vegetation damage. An example is the sacred fir (Abies religiosa) forests surrounding Mexico City, which have been heavily exposed to tropospheric ozone, a harmful pollutant, for over 4 decades. We developed a participatory monitoring system with which local community members and scientists generated data on ozone tree damage. Santa Rosa Xochiac rangers (13) used the digital tool KoboToolBox to record ozone damage to trees, tree height, tree ages, tree condition, tree position, and whether the tree had been planted. Thirty-five percent of the trees (n = 1765) had ozone damage. Younger trees had a lower percentage of foliage damaged by ozone than older trees (p < 0.0001), and asymptomatic trees tended to be younger (p < 0.0001). Symptomatic trees were taller than asymptomatic trees of the same age (R2c = 0.43, R2m = 0.27). Involving local communities facilitated forest monitoring and using digital technology improved data quality. This participatory system can be used to monitor forest condition change over time and thus aids restoration efforts driven by government or local communities’ interests, facilitating local decision-making. 相似文献
610.
目前 ,我国重点城市都在开展环境空气质量日报或预报工作 ,开展这一工作的基本条件之一是必须建立环境空气质量自动监测系统。由于我国目前的研制水平有限 ,空气质量自动监测系统基本上是靠引进国外技术及设备来完成的。而引进设备往往与我国的具体实际结合不够 ,尤其是在系统结构、数据采集、远程控制与诊断方面同我们的实际要求相去甚远。为此本文将围绕国内环境监测共同关注的环境空气质量自动监测系统及其设计的问题展开讨论 ,内容包括目前国内自动监测系统的现状 ;国外发展情况及趋势 ;自动监测系统结构与要求 相似文献