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151.
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
152.
酸性硫酸盐土的发育与分布存在着较大的时空变异,表现为空问分布的不连续性、发育时间的间断性、环境影响的级联性以及开发利用的风险性,因此往往给实际利用带来较大的困难。本文对酸性硫酸盐士的形成与发育特点、野外景观生态诊断以及酸性硫酸盐土的时空分布与演替模式等方面进行探讨,旨在使人们正确地认识酸性硫酸盐土,以便更有效地利用这类土地资源。 相似文献
153.
Chang Xuan Mao 《Environmental and Ecological Statistics》2007,14(4):473-481
Consider the removal experiment used to estimate population sizes. Statistical methods towards testing the homogeneity of
capture probabilities of animals, including a graphical diagnostic and a formal test, are presented and illustrated by real
biological examples. Simulation is used to assess the test and compare it with the χ2 test.
相似文献
Chang Xuan MaoEmail: |
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鉴于镉对水稻各种生理特征参数的影响具有复杂隐蔽性,导致冠层光谱特征变化微小,需要采用一些方法增强和提取隐含在光谱中的污染弱信息.在水稻冠层高光谱数据和各种实测生化参数的支持下,利用主成分分析、独立分量分析和分形分析技术从高光谱遥感数据中提取镉污染弱信息,获取水稻镉污染敏感光谱因子,包括第一主成分F1、独立分量ICA1和光谱分维D.利用3个敏感因子分别构建水稻镉污染一维诊断模型,获得较好的诊断效果.进一步将3个光谱因子进行组合构建二维诊断模型和三维诊断模型,使污染胁迫诊断结果更稳定直观. 相似文献
157.
我国先秦时期形成了较为系统的农业减灾救荒思想,它包含灾前预防思想、农业减灾思想和灾后救荒思想三大部分。中国古代的减灾和救荒两大思想体系由此成为有机整体,这在三代(夏、商、周时期)和春秋战国时期农业生产的转型发展过程中产生了积极的促进作用。研究这一时期的农业减灾救荒思想对于后世的防灾减灾极具借鉴意义。 相似文献
158.
Design of Intelligent Fault Diagnostic System (FDS) 总被引:1,自引:0,他引:1
This research work presents useful framework and mechanism for integrated fault diagnostic system, or FDS. The proposed system is composed of three major subsystems: fault detection, root cause and consequence analyzer, and maintenance analyzer. Learning mechanisms are proposed to extract knowledge about deviations/failure modes from real time process and equipment monitoring data. Fault semantic network is proposed to represent failure modes and fault propagation models as integrated with process and equipment models. Qualitative rules are defined and associated with fault semantic networks for practical Actual maintenance findings are used to tune training data for more accurate fault detection and root cause and consequence analysis. Case study is used to illustrate the proposed idea. 相似文献
159.
Chains of accidents, in literature generally referred to as domino effects, knock-on effects, cascade effects or escalation effects occur very infrequently but with disastrous consequences. There exist very few software packages to study such domino accidents in complex industrial areas and to forecast potential catastrophes caused by secondary order (involving a sequence of three installations submitted to two consecutive accidents), tertiary order or even higher order accidents. Moreover, available domino software focuses on risk assessment and on consequence assessment. None of these toolkits specifically addresses the prioritization of installation sequences in an industrial area in order to facilitate objective prevention decisions about domino effects. This paper describes the application of a new computer-automated tool designed to support decision-making on preventive and protective measures to alleviate domino effects in a complex surrounding of chemical installations. Using a holistic approach and thus looking at the entire industrial area as a whole, all sequences of three installations in the area are ranked according to their danger contribution to domino effects. An example of a cluster of chemical plants demonstrates the level of qualitative and quantitative input data required. The example is also used to explain the toolkit results, as well as the surplus value and the benefits for company safety managers and regulators. 相似文献
160.
An intensive sampling program had been undertaken in autumn (October, 2008) and winter (December, 2008 and January, 2009)
at urban (Xiamen University and Xianyue residential area), suburban (Institute of Urban Environment), industrial area (Lulian Hotel)
and background (Tingxi Reservoir) in Xiamen, Fujian Province, to characterize the atmospheric concentration and gas-particle phase
partitioning of PAHs. The average concentration of total PAHs in winter was almost 1.7 times higher than those in autumn. The log
scale plot of Kp versus sub-cooled liquid vapor pressure (P0
L) for all the data of autumn and winter season samples gave significantly
di erent slopes. The slope for the winter samples (–0.72) was steeper than that for the autumn samples (–0.58). The partitioning results
indicated that slope values varied depending on characteristics of specific site, source region and meteorological conditions which
play important roles in the partitioning of PAHs. In addition, local emission sources had a stronger e ect on partitioning results than
long-transported polluted plume. The sources of PAHs in five sampling sites in Xiamen also have been discussed initially. Diagnostic
ratios showed that the primary source of PAHs in urban, suburban and industrial area was from vehicle exhausts. While emission from
petrochemical factory and power plant was another main contributor to industrial area. 相似文献