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101.
102.
中国天然林资源保护工程综合评价指标体系与评估方法 总被引:1,自引:0,他引:1
天然林资源是国家重要的战略资源与生态资源,在维护国土生态安全、应对气候变化、保护生物多样性等方面发挥着不可替代的重要作用。作为覆盖范围最广、投资规模最大的天然林资源保护工程(简称天保工程)自2000年正式启动以来,对长江上游、黄河上中游地区以及东北、内蒙古、新疆、海南等重点国有林区的森林资源保护修复、区域生态环境改善及经济社会可持续发展等多方面都产生了巨大、深远影响。天保工程二期于2020年结束,全面定量评估天保工程的生态、经济和社会综合效益和国内外的巨大影响,可为全面推进我国天然林资源保护修复提供科技支撑,为后续政策修订提供决策依据。本文基于空间信息技术、样地调查、生态站观测、比较分析等手段,构建了适用于天保工程的综合评价指标体系与评估方法,涵盖森林资源、生态效益、社会经济效益、生态修复措施和政策设计5个方面,对全面贯彻落实国家生态文明战略和《天然林保护修复制度方案》具有重要的现实意义和深远历史意义,为开展全国性的重大生态工程评估提供借鉴和参考。 相似文献
103.
ODB基因在植物同源重组依赖性的DNA双键断裂修复过程中起重要作用,对植物诱变育种具有潜在的应用价值。克隆烟草NtODB基因并分析其表达特征为丰富ODB基因在同源重组DNA修复过程中的作用提供证据。为得到烟草NtODB基因序列,采用电子克隆技术获得该基因cDNA序列并克隆验证。进一步使用生物信息学方法分析该基因表达特征,对预测蛋白的理化性质、信号肽、高级结构等进行预测。生物信息学分析结果表明,NtODB基因开放阅读框包含579个碱基,蛋白含192个氨基酸残基,NtODB蛋白具有碱性和亲水性,主要定位于细胞质内;实时荧光定量PCR检测结果显示NtODB基因在不同组织中呈现组成型表达特征;亚细胞定位检测提示NtODB主要表达于细胞膜和叶绿体。NtODB基因的克隆与表达分析及其蛋白高级结构和理化性质的预测,可为进一步丰富ODB基因在同源重组依赖的DNA修复系统中的作用机制提供证据。 相似文献
104.
依托第四次全国中药资源普查工作,摸清马尾区药用植物资源种类、分布、重点中药材品种以及药材栽培等情况。根据第四次全国中药资源普查要求,通过实地调查、走访以及栽培基地调查等方法对马尾区药用植物资源进行调查,查阅相关资料确定野生药用植物的药用部位、生活型等。马尾区野生药用植物种类共计506种,隶属于132科360属,含2~5种的寡种科占绝对优势地位;草本为主要生活型,药用部位集中在根类和全草类;有福建省重点药材50种、特色药材22种。由于长期受人为干扰,马尾区原生植被破坏严重,药用植物种类较为贫乏。因此,可考虑林下种植中药改善土壤环境,实现中药资源可持续发展。 相似文献
105.
Debapriya Ghosh Manoj Kumar Mishra Sulagna Das Deepak Kumar Kaushik Anirban Basu 《Journal of neurochemistry》2009,110(3):1070-1081
4-Methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK) is a tobacco-specific procarcinogen. We have investigated whether NNK causes inflammatory upheaval in the brain by activation of resident microglia and astrocyte and result in bystander neuronal damage. We have carried out the work in both in vitro and in vivo models. We have found that treatment with NNK causes significant activation of mouse microglial (BV2) cell line as evident by increase in reactive oxygen species and nitric oxide level. Western blot analysis has showed increase in proinflammatory signaling proteins, proinflammatory effector proteins, and other stress-related proteins. Interestingly, increased levels of proinflammatory cytokines like interleukin (IL)-6, tumor necrosis factor-α, monocyte chemoattractant protein 1 (MCP1), and IL-12p70 are also detected. Work from our in vivo studies has demonstrated similar increase in proinflammatory signaling and effector molecules along with the proinflammatory cytokine levels, following NNK treatment. Immunohistochemical staining of the brain sections of NNK-treated mice reveals massive microglial and astrocyte activation along with distinct foci of neuronal damage. Both in vitro and in vivo results provide strong indication that NNK causes significant upheaval of the inflammatory condition of brain and inflicts subsequent neuronal damage. 相似文献
106.
107.
Shunhua Ding Qingtao Lu Yan Zhang Zhipan Yang Xiaogang Wen Lixin Zhang Congming Lu 《Plant molecular biology》2009,69(5):577-592
To investigate the possible mechanisms of glutathione reductase (GR) in protecting against oxidative stress, we obtained transgenic
tobacco (Nicotiana tabacum) plants with 30–70% decreased GR activity by using a gene encoding tobacco chloroplastic GR for the RNAi construct. We investigated
the responses of wild type and transgenic plants to oxidative stress induced by application of methyl viologen in vivo. Analyses
of CO2 assimilation, maximal efficiency of photosystem II photochemistry, leaf bleaching, and oxidative damage to lipids demonstrated
that transgenic plants exhibited enhanced sensitivity to oxidative stress. Under oxidative stress, there was a greater decrease
in reduced to oxidized glutathione ratio but a greater increase in reduced glutathione in transgenic plants than in wild type
plants. In addition, transgenic plants showed a greater decrease in reduced ascorbate and reduced to oxidized ascorbate ratio
than wild type plants. However, there were neither differences in the levels of NADP and NADPH and in the total foliar activities
of monodehydroascorbate reductase and dehydroascorbate reductase between wild type and transgenic plant. MV treatment induced
an increase in the activities of GR, ascorbate peroxidase, superoxide dismutase, and catalase. Furthermore, accumulation of
H2O2 in chloroplasts was observed in transgenic plants but not in wild type plants. Our results suggest that capacity for regeneration
of glutathione by GR plays an important role in protecting against oxidative stress by maintaining ascorbate pool and ascorbate
redox state. 相似文献
108.
Marjaana Suorsa Sari Sirpio Eva-Mari Aro 《植物生理学报》2009,(6):1127-1140
The NAD(P)H dehydrogenase (NDH) complex in chloroplast thylakoid membranes functions in cyclic electron transfer, and in chlororespiration. NDH is composed of at least 15 subunits, including both chloroplast- and nuclear-encoded proteins. During the past few years, extensive proteomic and genetic research on the higher plant NDH complex has been carried out, resulting in identification of several novel nuclear-encoded subunits. In addition, a number of auxiliary proteins, which mainly regulate the expression of chloroplast-encoded ndh genes as well as the assembly and stabilization of the NDH complex, have been discovered and characterized. In the absence of detailed crystallographic data, the structure of the NDH complex has remained obscure, and therefore the role of several NDH-associated nuclear-encoded proteins either as auxiliary proteins or structural subunits remains uncertain. In this review, we summarize the current knowledge on the subunit composition and assembly process of the chloroplast NDH complex. In addition, a novel oligomeric structure of NDH, the PSI/NDH supercomplex, is discussed. 相似文献
109.
广西河池地区鱼类资源调查及两支流的鱼类多样性比较 总被引:2,自引:0,他引:2
于1994年至2008年间,对广西河池地区的柳江水系和红水河水系进行了鱼类资源调查。依据实际调查,并结合以往文献记载,这两水系中分布的鱼类共有185种,分别隶属于9目21科107属。较以前调查,新增种类21种,包括1新属19新种。柳江水系分布的鱼类共有134种,分别隶属于8目19科88属。其中,鲤形目鱼类的种类最多,鲈形目鱼类次之,鲇形目鱼类第三,其他目的鱼类种类相对较少,仅1—3种。红水河水系分布的鱼类共有157种,分别隶属于8目20科101属。其中,鲤形目鱼类的种类最多,鲇形目鱼类次之,鲈形目鱼类第三,其他目的鱼类种类相对较少。红水河水系的鱼类多样性较柳江水系丰富,其主要原因为红水河流经区域喀斯特地貌发育,地下河流众多而且流域面积广,水量充沛。 相似文献
110.
The role of state forests in the conservation of the savannah environment of western Burkina Faso (West Africa) was assessed
by considering the customary and fundamental biological components of plant diversity. The focus is on the “ordinary biodiversity”
which constitutes the current environment of human populations and which generates their resources. Overall floristic composition,
α, β, γ diversities and species accumulation curves of landscape units were compared inside and outside protected areas. Common species
were identified according to their frequencies in landscape units and their local abundance. The occurrences of functional
(life form, dispersion, etc.) and human-valued (current uses, potential threats, etc.) traits were compared. Current land
uses outside protected areas have an unequal effect on the various components of plant diversity. Species richnesses and specific
structures were all the more altered for woody species as agricultural pressure is high; conversely, they were maintained
for herbaceous communities for which the proportion of wide-ranging species increased. The preservation of useful plant species
on cultivated lands was obvious for woody species with edible fruits but less tangible for timber and service wood. It was
deficient for species that furnish other non-wood products (e.g. leaves used as food or fodder), the conservation of which
may be jeopardized where anthropic pressure is high. Given current land uses and dynamics, maintaining conservation areas
in land use planning is crucial in order to preserve ordinary biodiversity.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献