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1.
U.D Chima  G. Vure 《林业研究》2014,25(4):915-921
The study evaluated the impact of crude oil pollution on natural regeneration of plant species in a major oil-producing community in the Niger Delta region of Nigeria. Three sites—unpolluted site(US), polluted and untreated site(PUS), and polluted and treated site(PTS)—were purposively chosen for the study. The seedling emergence method was used to evaluate soil seed banks in the various sites at two depths, 0 to 10 cm and 10 to 20 cm. Woody-plant species richness, abundance, and diversity were higher in the US seed bank than in the PUS and PTS seed banks. The highest number of non-woody plants was observed in the US, followed by the PTS, and then the PUS. Both species richness and diversity of non-woody plants were highest at the US, followed by the PUS, and lowest in the PTS. Woody species in the US seed bank were 87.5% and 80% dissimilar with those of the PUS and PTS at 0–10 cm and 10–20 cm respectively. No variation was observed between woody species in the PUS and PTS seed banks. Non-woody species at 0-10 cm US seed bank were 73.08% dissimilar with those of PUS at the two soil depths and 81.48/88.46% dissimilar with those of the 0–10/10–20 cm of the PTS respectively. At 10–20 cm, non-woody species of the US were 69.66% dissimilar with those from each of the two soil depths in PUS; and 73.91/81.82% dissimilar with those of 0–10/10–20 cm of the PTS respectively. Non-woody species variation between the PUS and PTS was higher at 10–20 cm than 0–10 cm. The poor seed bank attributes at the polluted sites demonstrates that crude oil pollution negatively affected the natural regeneration potential of the native flora because soil seed banks serve as the building blocks for plant succession. Thorough remediation and enrichment planting are recommended to support the recovery process of vegetation in the polluted areas.  相似文献   

2.
Carbon(C) dynamics are central to understanding ecosystem restoration effects within the context of Grain for Green Project(GGP). GGP stared in China since 2003 to improve the environment. Despite its importance, how total forest ecosystem C stock(FECS) develops following land-use changes from cropland to plantation is poorly understood, in particular the relationship of C allocation to pools. We quantified C pools in a chronosequence ranging from 0 to 48 years, using complete above- and below-ground harvests based on detailed field inventory. Stands were chosen along a succession sequence in managed plantations of Korean larch(Larix olgensis Henry.), a native planting species in the Lesser Khingan Mountains, Northeast of China. The FECS of Korean larch plantation(KLP) were dynamic across stand development, changing from 88.2 Mg·ha-1 at cropland, to 183.9 Mg·ha-1 as an average of forest C from 7- through 48-year-old plantation. In a 48-year-old mature KLP, vegetation comprises 48.63% of FECS and accounts for 67.66% of annual net C increment(ANCI). Soil is responsible for 38.19% and 13.53% of those, and with the remainders of 13.18% and 18.81% in down woody materials. Based on comparisons of our estimate to those of others, we conclude that afforestation of Korean larch plantation is a valid approach to sequester carbon.  相似文献   

3.
The term allelopathy refers to biochemical interaction between all types of plants including microorganisms through pro-duction of chemical compounds that escape into the environment and exist widely in Quercus L. The development of investigations into types of allelochemicals, their compounding and spreading pathways, as well as expression of allelopathy in Quercus L. are re-viewed in this paper. We have closely and systematically emphasized the functional mechanisms of allelopathy in forest plants for our next research project on allelopathy in Quercus L.  相似文献   

4.
The cell cycle is an important research field in cell biology and it is genetically and developmentally regulated in animals and plants. The aim of this study was to review knowledge about the biochemical regulation of the cell cycle by plant growth regulators through molecular checkpoints that regulate the transition from G0-G1-S-phase and G2-M in higher plants.Recent research has shown that zeatin treatment led to the up-regulation of CycD3 in Arabidopsis. Benzyladenine treatment can also shorten the duration of S-phase through recruitment of latent origins of DNA replication. Kinetin is involved in the phosphoregulation of the G2-M checkpoint; the major cyclin-dependent kinase (Cdk) at this checkpoint has recently shown to be dephosphorylated as a result of cytokinin treatment, an effect that can also be mimicked by the fission yeast Cdc25 phosphatase. Gibberellic acid (GA) treatment induces internode elongation in deepwater rice, this response is mediated by a GA-induced up-regulation of a cyclin-Cdk at the G2-M checkpoint. Recent evidence has also linked abscisic acid to a cyclin-dependent kinase inhibitor. A new D-type cyclin, recently discovered in Arabidopsis may have a key role in this process. A brief review on plant growth regulator-cell cycle interfacing during development and a cytokinin-induced continuum of cell cycle activation through the up-regulation of a plant D-type cyclin at the G1 checkpoint and the phosphoregulation of the Cdk at the G2/M checkpoint had been concluded. This review could be valuable to research on cell and developmental biology in plants.  相似文献   

5.
The study tour group, organized by the project team of Forestry and Society Network (FSN) of the Institute of Scientific and Technologic Information, Chinese Academy of Forestry paid a visit to Sino-Nether-lands Poverty Relief Community Forestry Project (the Project) in Heshan County of Anhui Province on 18 - 21 July, 2001. The group consisted of 23 members, including Director of Mountainous Area Development Office (MADO) of Planning Department, State Forestry Administration (SFA), Chief of Integrated Division of the Department of Science and Technology, SFA, officials from forestry departments of Hebei, Zhejiang and Guizhou Provinces, professors of forestry  相似文献   

6.
Pistil Development in 2 Types of Flowers of Xanthoceras sorbifolia   总被引:1,自引:0,他引:1  
In order to investigate flower development and female abortion during sex differentiation ofXanthoceras sorbifolia,anatomical observations and comparative study on differential proteins were carried out in different developmental stages of two types of flowers of this species. It was found that the selective abortion happened in male flower before the formation of megasporocyte. Special proteins related to the female abortion were found through 2-dimensional electrophoretic analysis. Protein Al(14.2 kD)only existed in florescence of male flower, while B1 (13.7 kD) and B2 (18.2 kD) disappeared in that stage of male flower. They were all considered to be relative to pistil abortion ofXanthoceras sorbifolia.  相似文献   

7.
This study briefly examines the role of forest in poverty reduction in sub-Saharan Africa in the 21st century despite the effect of deforestation and degradation. This sub region is rated as the second region with the highest 3roportion of poor people globally, i.e., 325 million people. Income in the sub region has fallen below the World Bank ;)overty line of $1.25 per day for developing countries. In fact 45% of the population live on less than $1 per day, with Lwo thirds of the population living in rural areas and small-holder farmers accounting for 80% of the poor. Although about 1.6 billion people live on $1-2 per day, signifying improvement in living standards, it is incomparable to income levels in developed countries. The region is therefore characterized by hunger and starvation, diseases, illnesses and under development. In the sub region, the Gini coefficient is 0.44, indicating a high incidence of poverty. Countries worst hit by absolute poverty in the sub region are Nigeria, Mall and the Central African Republic. Consequently, there is an urgent need to improve the welfare of the population of this sub region through available natural resources, such as forests, where modern technology also still lags far behind. It is therefore recommended that forest policy in the sub region be Focused on forestry initiatives that will encourage access to forest resources and in turn increase the well-being of the 3oor through the natural bounty of the goods and services from the forest. Furthermore, forest food consumption must 3e encouraged among the rural poor through appropriate agroforestry practices, along with enhanced literacy, as well as ~ducation for processing and marketing of forest products in regional markets.  相似文献   

8.
Changbai Mountain forest area is not only is a national timber base but also a green ecological defense for Songliao Plain of NE China. The Natural Forest Protection Project of this area has an important bearing on the social and economic sustainable development of Jilin Province or even the whole forest area in NE China. This paper summarized general conditions of natural forest in Changbai Mountain state-owned forest area and put forward six problems need to be urgently solved and five strategic suggestions on natural forest protection and sustainable management.  相似文献   

9.
Wei Tang  Anna Y.Tang 《林业研究》2019,(5):1555-1568
RNA-seq and single-cell genomic research emerge as an important research area in the recent years due to its ability to examine genetic information of any number of single cells in all living organisms.The knowledge gained from RNA-seq and single-cell genomic research will have a great impact in many aspects of plant biology.In this review,we summary and discuss the biological significance of RNA-seq and single-cell genomic research in plants including the single-cell DNA-sequencing,RNA-seq and single-cell RNA sequencing in woody plants,methods of RNA-seq and single-cell RNA-sequencing,single-cell RNA-sequencing for studying plant development,and single-cell RNA-sequencing for elucidating cell type composition.We will focus on RNA-seq and single-cell RNA sequencing in woody plants,understanding of plant development through single-cell RNAsequencing,and elucidation of cell type composition via single-cell RNA-sequencing.Information presented in this review will be helpful to increase our understanding of plant genomic research in a way with the power of plant single-cell RNA-sequencing analysis.  相似文献   

10.
Mikania cordata, an invasive weed is becoming a problem in the secondary degraded forests and plantations of Bangladesh, not only competing with but also releasing allelochemicals to cultivated crops. Allelopathic effects of the leaves of M. cordata were investigated through an experiment in the green house of the Institute of Forestry and Environmental Sciences, University of Chittagong, Bangladesh. Five economically important agricultural crops(Oryza sativa L., Triticum aestivum L., Vigna sinensis L., Abelmoschus esculentus L. and Amaranthus tricolor L.) and three forest crops(Acacia auriculiformis A.Cunn. ex Benth. Hook, Albizia procera(Roxb.) Benth.,and Paraserianthes falcataria(L.) Nielson) were used as bioassay species. Experiments were conducted on trays at an average room temperature 27 °C. The effects of different concentrations of leaf extracts were compared to controls. Water soluble allelochemicals of M. cordata inhibited the germination and initial growth of the tested agricultural and forest crops. Germination percent of forest crops declined with increasing concentration of extracts.The inhibitory effect on root elongation of forest crops was pronounced, whereas a stimulatory effect was found on P.falcataria up to a concentration of 25 %. Abelmoschus esculentus showed poor germination(%) and low shoot development(0.5 cm) and no development of taproot or lateral roots at treatment of 100 % concentration. Theinhibitory effect was proportional to the concentrations of the extracts with higher concentrations producing stronger inhibitory effects. Lower concentrations showed some stimulatory effect. The inhibitory effect was pronounced in root and lateral root development rather than germination or shoot development of the crops. Mikania cordata should be eradicated for healthy growth and development of the forest and adjacent agricultural crops.  相似文献   

11.
Addressing climate change has become a common issue around the world in the 21st century and equally an important mission in Chinese forestry.Understanding the development of monitoring and assessment of forest biomass and carbon storage in China is important for promoting the evaluation of forest carbon sequestration capacity of China.The author conducts a systematic analysis of domestic publications addressing"monitoring and assessment of forest biomass and carbon storage"in order to understand the development trends,describes the brief history through three stages,and gives the situation of new development.Towards the end of the 20th century,a large number of papers on biomass and productivity of the major forest types in China had been published,covering the exploration and efforts of more than 20 years,while investigations into assessment of forest carbon storage had barely begun.Based on the data of the 7th and 8th National Forest Inventories,forest biomass and carbon storage of the entire country were assessed using individual tree biomass models and carbon conversion factors of major tree species,both previously published and newly developed.Accompanying the implementation of the 8th National Forest Inventory,a program of individual tree biomass modeling for major tree species in China was carried out simultaneously.By means of thematic research on classification of modeling populations,as well as procedures for collecting samples and methodology for biomass modeling,two technical regulations on sample collection and model construction were published as ministerial standards for application.Requests for approval of individual tree biomass models and carbon accounting parameters of major tree species have been issued for approval as ministerial standards.With the improvement of biomass models and carbon accounting parameters,thematic assessment of forest biomass and carbon storage will be gradually changed into a general monitoring of forest biomass and carbon storage,in order to realize their dynamic monitoring in national forest inventories.Strengthening the analysis and assessment of spatial distribution patterns of forest biomass and carbon storage through application of remote sensing techniques and geostatistical approaches will also be one of the major directions of development in the near future.  相似文献   

12.
The amount of carbon returned through litterfall and its seasonal pattern were studied in a natural forest of Castanopsis kawakamii (NF) and adjacent monoculture plantations of C. kawakamii (CK) and Chinese fir (Cunninghamia lanceolata) (CF) in Sanming, Fujian Province, China. Mean annual carbon return through total litterfall over 3 years (from 1999 to 2001) was 5.097 t穐m2 in the NF, 4.337 t穐m2 in the CK and 2.502 t穐m2 in the CF respectively. Of the total carbon return in the three forests, leaf contribution accounted for 58.96%, 68.53% and 56.12% and twig 24.41%, 22.34% and 26.18%, respectively. The seasonal patterns of carbon return from total litterfall and leaf-litter were quite similar among the three forests. A peak of carbon input from litterfall in the NF and the CK occurred in spring except for the highest annual C return through branch litter of the NF in summer, while the CF showed the maximum C return in summer. The results of this study demonstrate that the natural forest has a greater C return through litterfall than monoculture plantations, which is beneficial to the increase of soil organic matter storage and the maintenance of soil fertility.  相似文献   

13.
Assessment of regional forest carbon stocks and underlying controls is critical for guiding forest management in the context of carbon sequestration. We investigated the variations in tree biomass carbon stocks relating to forest types, and estimated the total tree biomass carbon stocks and projected gains through natural stand development by 2020 and 2050 in the Daqing Mountain Nature Reserve based on Category II data of the Forest Inventory of Inner Mongolia for the period ending 2008. Over a total area of 388,577 ha,this nature reserve currently stores an estimated 2221 Gg C in tree aboveground biomass alone, with potential to grow by more than 30 % to reach 2938 Gg C by 2020 and nearly double to 4092 Gg C by 2050 through natural development of the existing forest stands. The tree biomass carbon density and potential gain in tree biomass carbon stocks vary markedly among forest types and with stand development.The variations in the potential change of tree biomass carbon density for the periods 2008–2020 and 2008–2050 among forest types partly reflect the varying relationships of tree biomass carbon density with stand age for different tree species, and partly are attributable to variations in the stand age structure among different forest types. Of the major forest types, the ranking of projected changes in tree biomass carbon density are not consistent with variations in the relationship between tree biomass carbon density and stand age, neither are they explainable by variations in stand age structures, implying the interactive effect between forest type and stand dynamics on temporal changes in tree biomass carbon density. Birch rank highest for future biomass carbon sequestration because of its dominance in cover area and better age structure for potential gain in tree biomass carbon stocks. Poplar and larch were out-performers compared to other forest types given their greater contribution to total tree biomass carbon stocks relative to their distributional areas. Findings in this study illustrate that protection and proper management of under-aged forests can deliver marked gains in biomass carbon sequestration. This is of great importance to policy-makers as well as to scientific communities in seeking effective solutions for adaptive forest management and mitigation of anthropogenic greenhouse gases emissions using forest ecosystems.  相似文献   

14.
The historic development of forest certification was firstly reviewed in order to understand how forest certification has developed throughout the world.The characteristics of forest certification were analyzed in details,including the essence of forest certification,approach of forest certification,structure of forest certification and development processes of forest certification standards.Then,the forest certification development in China was reviewed,including background,basic principles and objectives and main tasks.Based on the reviews on forest certification,recommendations were given so as to greatly boost the development of forest certification in China.  相似文献   

15.
In this study, we developed a comprehensive index system for forestry sustainability of Heilongjiang Province, which includes forest resources sustainability,sustainable economic development, sustainable social development and sustainable advancement in science and technology. Based on this system and the regional forest development, we further evaluated the sustainability of Heilongjiang Province for year 2008–2013. The results show that even though the regional forestry has been preliminarily on the track of sustainable development, it is fragile. Four indicators, e.g. soil and water retention rate,forest stand growth(per unit area), the proportion of national investment and the annual carbon sequestration have important impact on the sustainability, with a weight of 39.0 % in all the indicators. We also analyzed the factors hindering the sustainable development. It turns out that soil and water retention rate, forest stand growth(per unit area),the proportion of science and technology funds, per capita GDP and the proportion of the tertiary industry production are the main factors hindering regional sustainable development, which accounts for 50.94 % of the total obstacle degrees in the system. At last, we discussed how to promote the regional sustainable development from the perspectives of forest resources sustainability, economic development sustainability, society development sustainability and the sustainable advancement of science and technology.  相似文献   

16.
Studies on Heavy Metal Pollution in Soil—Plant System:A Review   总被引:2,自引:0,他引:2  
Heavy metal pollution in soil-plant system is of major environmental concern on a world scale and in China in particular with the rapid development of industry.The heavy metal pollution status in soil-plant system in China,the research progress on the bioavailability of heavy metals (effecting factors,extraction methods,free-ion activity model,adsorption model,multivariate regression model,Q-I relationship,and compound pollution),and soil remediation are reviewed in paper.Future research and monitoring is also discussed.  相似文献   

17.
Basedon the results of monitoring the environment of China National Afforestation Project (NAP) and the investigation on insect pests and diseases in 1.2 million ha of plantations, the author elaborates the areas, species and causes of insect pests and diseases occurring in the project's areas and provides fundamental theory for guiding environmental protection and plantation establishment in a sound way. Since the project's activities strictly follovved the guideline of environmental protection in past five years, little losses were caused by some commonly insect pests and diseases.  相似文献   

18.
Forest Resources and Environment in China   总被引:1,自引:0,他引:1  
With a vast territory, China is rich in forest resources and diversified environments. The changes in forest resources have a direct bearing on environmental quality. The paper gives a detailed account of the dynamic change in forest resources in China, including the overall process of forest evolution, the status quo and features of the existing forest resources and the development and use of major forest resources. In addition, it analyses the current situation of China's environment and explores the main contributing factors based on the overall environmental situation. In order to achieve sustainable management of forest resources and improve the environment in China, the Chinese government attaches great importance to the protection and development of forest resources as well as environmental development and improvement. The paper gives an overview of the thinking for sustainable forest resource and environmental development in the future and current focus of efforts.  相似文献   

19.
Choosing optimum softening process and exploring the factors affecting dimensional stability and their changing laws can be able to provide technological support for development of curving furniture. The total rubber wood samples were 112 [220 mm (longitudinal) × 17 mm (radial) × 8 mm (tangential)], and they were softened by boiling water and bent through using curved molds in the test. The optimum softening process was selected according to MOR value of the samples. Some affecting factors which influenced ...  相似文献   

20.
With rapid urbanization inChina, cities/towns continueto expand in size, ecological and environmentalproblems emerging during the process of urbanizationare becoming increasinglyevident.Urbanization movesforward rapidly, and any mistake in the design ofurban development would cause irreversible loss tothe country because of large investment in urbanenvironment development. According to the currentstatus of urban environment development in China,the available technical resources are far from me…  相似文献   

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