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81.
Patrycja Przewo
na Krzysztof Mczka Marcin Mielewczyk Adam Inglot Piotr Matczak 《Ambio》2022,51(9):2043
Policies and strategies for tree management and protection on a national, regional, and local level have not sufficiently considered differences between rural and urban areas. We used expert knowledge to compare rural and urban areas in a case study evaluating the relative importance of ecosystem services (ES) in policy development. The Analytic Hierarchy Process (AHP) and focus group discussions were used to rank 17 ES, representing four classes of services: provisioning, regulating, habitat, and cultural. The results indicated that effective protection strategies, beyond simply increasing general tree cover, should consider specific benefits trees provide to local communities. We discuss the role of objective prioritization of ES delivered by trees in urban and rural areas and their consequences for decision-making processes.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01722-2. 相似文献
82.
利用ICP-MS定量测定了温岭市电子垃圾拆解地区的大灰藓及樟树叶中的12种金属元素的含量,对比分析了两种指示生物对不同金属元素的富集情况.结果显示,不同地区样品中的所有金属含量呈现污染区对照区的趋势,其中苔藓中As、Cr、Mn、Se、V和Cd,樟树叶中Cr、Cu、Ni、Se、Sb和Cd的含量呈现重污染区轻度污染区对照区的趋势.拆解区中樟树叶中除Mn以外的金属总含量(所有金属含量之和)要低于苔藓.除Mn、Cr和Se以外的其它9种金属在苔藓中的含量要显著高于樟树叶中的金属含量(p0.05),但苔藓中金属含量的标准偏差要大于樟树叶.由污染因子(pollution factor)的结果表明苔藓及树叶样品中的金属Sn、Sb及Cd的污染因子最高;另外,研究通过比较树叶样品的不同预处理过程对最终含量测定的影响,发现经超纯水清洗的树叶样品中所有金属浓度要明显低于未经清洗的样品,并且标准偏差较低,数值稳定性好.主成分分析结果表明,Co、Cr、Ni、Pb、Sn及Cd为密切相关的一类元素,主要来源于电子废弃物拆解行为,而Mn、As及Se为第二类元素,主要来源于地质因素. 相似文献
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以4年生蒙古栎(Quercus mongolica) 幼树为实验材料,分别于2007,2008年6~9月采用开顶箱法,研究了高浓度CO2和O3及复合作用对蒙古栎叶片光合量变化和生长的影响.结果表明,高浓度O3处理下蒙古栎叶片日光合总量降低, 单叶鲜重、干重和单叶面积均有所下降,对蒙古栎叶片生长产生抑制.高浓度CO2处理下,蒙古栎叶片干、鲜重和单叶面积均高于对照,其中2007年差异显著,日光合总量总体高于对照.2种气体复合作用处理下,蒙古栎日光合总量、单叶鲜重、单叶干重、单叶面积均低于对照,且高于O3单独处理,说明高浓度CO2可以通过减缓O3对植物光合的抑制,进而减少O3伤害,缓解生长抑制. 相似文献
85.
Metribuzin, a triazinone herbicide, is heavily used within the expansive Nzoia River Drainage Basin in Kenya for the optimization of sugarcane yields. For field experiments, soils were spiked with metribuzin and amended with filter mud compost and Tithonia diversifolia leaves. Soils with history of metribuzin application (48 months) were also spiked with metribuzin but not amended with the organic materials. Degradation of metribuzin for the three variants was followed for a period of 102 days. Repeated exposure of metribuzin to soil and addition of filter mud compost to soil enhances the degradation of metribuzin with half dissipation times of 31 and 25 days. In soil amended with Tithonia diversfolia leaves, the half dissipation time was 32 days while in the control (unamended non history soil), it was 36 days. Laboratory studies showed that soil sterilization slowed the degradation of metribuzin, with a half dissipation time of 154 days. This confirmed that metribuzin was biochemically degraded in soil by an adapted community of microbes. 相似文献
86.
宜宾植被为亚热带常绿阔叶林,植物资源十分丰富,目前对树叶开发利用主要是茶叶、挥发油、蚕桑、中药材等。本文论述了宜宾植物资源开发的种类、经济效益及其前景。 相似文献
87.
Richard Reader 《Environmental management》1988,12(6):803-808
To help determine whether plants should be grouped into guilds for environmental impact assessment, the responses of six members of a guild of deciduous forest herbs to selective tree harvesting were compared. Harvesting operations themselves (tree cutting and skidding) had little effect on five of the six species but the sixth species decreased more in cut plots than in uncut plots. Subsequent microclimatic changes, resulting from tree cutting, also affected guild members differently. In the first year after cutting, two species increased more in cut plots than in uncut plots, while three other species did not change in frequency of occurrence and the sixth species decreased more in cut plots than in uncut plots. This inconsistent response of guild members to tree harvesting suggests that caution should be exercised in using guilds to assess plant response to environmental change. 相似文献
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植物与周围环境不断进行着气体交换,当外界大气环境发生变化时,就会对植物产生影响,这种影响会在植物体有关部位以各种形式反映出来.研究表明,植物中含硫量与大气SO2浓度呈现出密切相关性,因此,可以通过植物含硫量来反映大气SO2的污染状况. 相似文献