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1.
林改使红河州山区农民重新找回了曾经失落的希望,广大群众植树造林的热情高涨了,管护山林的意识增强了,依靠山林致富的愿望强烈了。  相似文献   

2.
林权管理制度改革破解了制约集体林业发展的体制性障碍,林业发展活力明显增强。一是充分激发了农民造林、育林、护林的积极性,推动了生态建设和保护;二是解放和发展了林业生产力,发挥了林地资源的潜力,促进了农民的增收致富;  相似文献   

3.
指出了在很长的一段时间内,我国以破坏生态环境做为代价,虽然促进了我国经济的快速发展。但是导致了我国的环境受到了严重的污染。从大气污染治理形势及问题进行了详细探讨,分析了在治理大气污染时存在的问题,根据原因,提出了科学合理的解决方案。  相似文献   

4.
森林生态效益补偿是国家为了巩固生态建设成效,对林权所有者和使用者进行适当补助的惠民政策,自实施以来得到了林区广大群众的拥护和支持,生态得到了保护和发展,林农得到了实惠。本文在对黔南州公益林管理现状进行了深入调研的基础上,分析了黔南州公益林管理存在的问题,并提出了解决问题的办法及建议,促进了公益林管护水平的提高。  相似文献   

5.
树活百千年而无语,默默地装点着群山、河流、田野、村庄与城市。树多就成林,林大即为森,巍巍群山有了茂密的树木,才会有长流不息的清清溪水滋润着的田野、村庄与城镇。有了树就有了水,有了水就有了田,有了田就有了粮,有了粮就有了人。可见,树与人类的生存有着密切的关系。森林,对于人类的重要性不言而喻,我们的城市也需要树木来装点。  相似文献   

6.
园林树木养护的措施与方法   总被引:3,自引:0,他引:3  
指出了园林树木养护工作的重要性,分析了园林树木养护存在的问题,提出了相关理论指导,探讨了园林树木养护的具体措施.  相似文献   

7.
花团锦簇     
从2001年到2007年,北京市政府大力加强城市园林绿化工作。城市园林绿地增加了1万公顷,树木增加了2271万株,草坪增加了4653万平方米,大大改善了市区的生态环境,使市民亲身感受到了绿色奥运带来的实惠。城市增添了绿色,市民增加了氧吧。  相似文献   

8.
鄂赣地区竹林土壤与植物营养特性及其信息化管理技术   总被引:1,自引:0,他引:1  
文章介绍了作者近年来在鄂赣地区进行的竹林土壤与植物营养特性及其信息化管理技术研究的成果:初步摸清了湖北、江西2省竹类主产区竹林生长和养分管理现状,明确了存在的问题;系统研究了湖北、江西2省竹类主产区土壤营养状况;建立了毛竹林土壤养分丰缺指标和叶片营养诊断指标;摸清了毛竹主产区土壤养分限制因子;提出了较适宜的毛竹叶片营养诊断技术;系统开展了毛竹林土壤养分空间变异特性的研究,提出了湖北、江西2省竹类主产区竹林全营养优化施肥配方和配套施肥技术;建立了毛竹林优化施肥的计算机管理系统。  相似文献   

9.
《陕西林业》2008,(1):19-20
陕西省林学会第十次会员代表大会2月23日在西安召开。中国林学会、省科协、省民间组织管理局领导参加了会议并作了讲话。会议听取并通过了上届理事会代理事长高永民作的题为《深化改革开拓刨新努力开刨学会工作的新局面》的工作报告;表决通过了《陕西省林学会章程》部分条文修正案;选举产生了新一届理事会理事、理事长、副理事长、秘书长,新当选的理事长郝福财即席作了就职答谢发言。张社年厅长参加了会议并作了重要讲话。  相似文献   

10.
为了准确反映城市生态系统的基本状况,设计了评估指标体系,利用数据仓库技术,构建了采集指标数据的网络系统,确定了数据仓库的体系结构,规划了数据维表和事实表;在此基础上形成了数据仓库的星形模型,搭建了评估平台,应用结果令人满意。  相似文献   

11.
野生动物所有权是所有权的一种,它与其他所有权的区别在于客体的不同。文章阐述了野生动物的内涵,分析了野生动物的分类和野生动物与野生动物资源的区别。在明确野生动物含义的基础上,提出了野生动物所有权的概念,深入论述了野生动物所有权与野生动物资源所有权的差异和联系,并对野生动物所有权的主体、客体、内容进行了分析。  相似文献   

12.
Senbeta  Feyera  Teketay  Demel  Näslund  Bert-Åke 《New Forests》2002,24(2):131-145
Regeneration of native woody species was studied in the plantations and the adjacent natural forest at Munessa-Shashemene Forest Project Area, Ethiopia. The aim of the study was to test the hypothesis that tree plantations foster regeneration of native woody species. A total of 60 plots, having 10 × 10 m area each, were studied in monoculture plantations of 4 exotic species (Cupressus lusitanica, Eucalyptus globulus, E. saligna, Pinus patula) and an adjacent natural forest. Ages of the plantations ranged between 9 and 28 years. Soil seed bank analysis was also undertaken from soil samples collected in each of the 60 plots to examine the similarity between the soil seed flora and aboveground vegetation. A total of 56 naturally regenerated woody species were recorded beneath all plantation stands with densities ranging between 2300 and 18650 individuals / ha in different stands. There was a significant difference among plantation stands with regard to understorey density (standard deviation: 4836 ± 1341). Vegetation diversity was assessed through analyses of floristic composition, species richness and abundance. Generally, seedling populations were the most abundant components of the regeneration in most of the plantation stands, forming 68 % of the total regeneration count in all stands. A total of 77 plant species represented by 44 herbs, 13 woody species, 8 grasses and 12 unidentified species were recorded in the soil seed bank from all stands. Similarity between the soil seed bank and aboveground flora was very low implying that the role of soil seed banks is negligible rather dispersal plays an important role in the process of regeneration. These results support the concept that forest plantations can foster the regeneration of native woody species, thereby increasing biological diversity, provided that there are seed sources in the vicinity of the plantations.  相似文献   

13.
在延安对刺槐、油松、侧柏纯林及刺槐 侧柏、刺槐 油松混交林等几种黄土高原主要人工林群落外貌结构、林下植物多样性特征进行了研究.结果表明:混交林群落外貌结构较为复杂,林下植物群落类型各不相同;林下植物的Simpson多样性指数和Shnnon-wiener多样性指数分别为0.902 57~0.674 88和2.012 88~1.479 67,刺槐 油松林最高,16年生刺槐纯林最低;32年生刺槐纯林林下植物优势度最高者是糙隐子草,16年生刺槐纯林则为牡蒿,其它林型都是铁杆蒿;本地区选择防护林类型时,应优先选择刺槐 油松或刺槐 侧柏混交,对已有的成熟或衰退刺槐纯林可采取择伐萌蘖抚育,并间植油松或刺柏,形成针阔混交林.  相似文献   

14.
Growing Acacia albida as a permanent tree crop, on farmlands with cereals, vegetables and coffee underneath or in between, is an indigenous agroforestry system in the Hararghe highlands of Eastern Ethiopia. However, there is practically no systematic record or data on the merits and benefits of this practice.The paper presents the results of an investigation into the effects of the presence of A. albida on farmlands on the yield of maize (Zea mays L.) and sorghum (Sorghum bicolor L. Moench). Twenty seven plot pairs each consisting of one plot underneath the A. albida foliage cover and the other in the open, away from the tree-on farmers' fields, in a 40 km radius around the Alemaya College of Agriculture, were sampled and the yield components analyzed. A statistically significant increase in crops yields by 56% on average was found for the crops under the tree canopies compared to those away from the trees. This increase was caused by the improvement in 1000 grain weight and number of grains of plants under the tree, indicating that the trees enhanced the fertility status of the soil and improved its physical conditions in terms of crop growth.Additional benefits from the A. albida trees include supply of fuelwood and fodder. Quantitative estimates of these outputs as well as their monetary values are presented in the paper. However, in order to realize these benefits to a discernible extent, higher stand densities of the tree than at present are required.Based on an enquiry about the farmers attitude towards A. albida, the prospects for an extension of this promising agroforestry technique are discussed against the background of the state and trends of development of agriculture in the area. It is surmised that despite some shortcomings like the relatively slow and highly variable growth of A. albida and a conflict with the spreading cultivation of Ch'at (Catha edulis Forsk.), the prospects of extension of this technique are good. It is recommended that its propagation should be incorporated into the programmes of the extension agencies of the various governmental agencies concerned with land use.  相似文献   

15.
油茶病虫害发生的现状及其环境因子研究   总被引:1,自引:0,他引:1  
对国内油茶病虫害发生相关研究进行了总结,分析了我国油茶病虫害的发生现状;结合油茶的地理分布、生态学特性和油茶病虫害的发生种类,提出与油条病虫害发生相关的环境因子.通过掌握环境因子的变化提高预测、防治油茶病虫害发生的频率,从而提高油茶的产量.  相似文献   

16.
The dynamics of K, Ca, and Mg were investigated during the decomposition of 14 litter types over a 3-year period on the upper and lower parts of a forest slope in a cool temperate forest in Japan. Potassium dynamics were divided into initial leaching phase and late phase. Initial K concentrations for the initial phase were correlated with the rate of decrease in K concentration during the initial phase. The late phase was characterized by seasonal fluctuations in concentration: K concentration increased from April to November and decreased during the winter period. The pattern of change in Ca concentration was divided into initial increase phase and late decrease phase in some litter types, or consisted of the late phase only in other litters. Calcium concentration of the initial litter was not predictable for the pattern of change in Ca concentration nor the rate of change in Ca concentration during the initial phase. Initial Ca concentration for the late phase was correlated with the rate of change in Ca concentration during the late phase. The pattern of change in Mg concentration was divided into initial leaching phase and late immobilization phase. Initial Mg concentration for the initial phase was correlated with the rate of change in Mg concentration during the initial phase. At the lower site, initial Mg concentration for the late phase was correlated with the rate of change in Mg concentration during the late phase, while such a relationship was not observed at the upper site. Concentrations of K, Ca, and Mg showed a convergent trend at the end of the study period. The final concentration differed between the upper and lower sites.  相似文献   

17.
采集农田、林地和盐碱地不同类型的土壤样本,采用偏最小二乘法结合OSC方法建立土壤有机质反演模型,运用交叉验证和外部验证相结合的评价方法进行比较分析。结果显示:采用平滑+MSC+OSC方法对光谱进行预处理,可以提高预测模型的精度。OSC因子个数和PLS主因子个数分别为6和4时,交叉验证决定系数R2为0.990 1,均方根误差为0.297 5,外部验证决定系数R2为0.926 1,均方根误差为0.283 6,模型达到最优。表明对光谱进行OSC预处理后建模是可行的,OSC降低与浓度阵无关的光谱信号,并且减少建立模型的主因子个数,进一步提高模型的精度和稳定性。  相似文献   

18.
Martínez Pastur  G.  Arena  M.  Curvetto  N.  Zappacosta  D.  Eliasco  E. 《New Forests》2003,26(3):201-215
In vitro rooting constitutes a difficult step during the micropropagation process of forest species. The successive media culture technique represents one way to overcome this barrier and includes modifying physical (e.g. photoperiod) and chemical (e.g. flavonoids) factors during the rooting phases. The aim of this study was to obtain a successive media protocol based on the incorporation of flavonoids during the in vitro rooting of Nothofagus nervosa. The factors evaluated were the type, concentration, and combination of flavonoids in relation to the rooting phases, the presence of IBA in the culture medium, the photoperiod, and the effect of flavonoids on total tissue peroxidase activity. The photoperiod used included a darkness period during the rooting induction stage and the presence of 0.61 µMIBA in the culture medium. The results showed that flavonoid incorporation at a concentration of 20 µM accelerated the appearance of roots and improved the quality of the already formed ones. Each type and concentration of flavonoid produced different responses, with (±)naringenin giving the best results. The latter caused a peak in the peroxidase activity that was absent in the control treatments. This work allowed identifying an optimized rooting protocol through a successive media culture technique that improved the speed of appearance, as well as the quantity and quality of roots for a single N. nervosa clone.  相似文献   

19.
Dehesas are an agrosilvopastoral system that has enhanced the maintenance of an extraordinarily high biodiversity. The traditional use is characterized by mixed livestock raising at low stocking densities, employment of hardy regional breeds and an elaborated maintenance and exploitation of holm oaks. Livestock production has traditionally been accompanied by arable systems with long rotations and closed nutrient cycles without external inputs of fodder, fertilizers and agro-chemicals. Modern trends are a specialization toward lamb and beef production and the employment of intensive techniques like free-range grazing at high stocking levels or crossbreeding with high-performance breeds. A model income statement shows that livestock create an income of 49.91 US$ per ewe per year on an average basis. The central problem for the continuity of the dehesas is the gradual decay of the tree canopy. Intensification of agricultural production and the abandonment of traditional grazing practices additionally threaten biodiversity within the dehesas. The authors suggest the foundation of a biosphere reserve in Cuatro Lugares as a framework for a sustainable development of the dehesas.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

20.
本文对木材热值的测定方法进行了研究。为了提高试验的精确度,改进了试样的容器;减少试样辅助添加剂引入的误差;考虑了含脂材挥发物对热值的影响,提出了一个实际通用的测试方法。通过对二十四种样木的测试,综合分析了测试误差、生态差异以及营林因子等的影响,对薪材热值的树种间差异和生态因子对热值变异时影响进行了研究。  相似文献   

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