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1.
报道我国5属:坛花兰属Acanthephippium、毛兰属Eria、沼兰属Malaxis、鸢尾兰属Oberonia、长喙兰属Tsaiorchis,5种兰科植物镶囊坛花兰Acanthephippium striatum、马齿毛兰Eria szetschuanica、小沼兰Malaxismicrotatahtha、小叶鸢尾兰Oberonia japonica、长喙兰Tsaiorchis neottianthoides在西藏、江西和湖南的新地理分布点,同时补充叉喙兰和小叶白点兰在贵州和湖南的具体分布点.凭证标本保存于中国科学院华南植物所标本馆(IBSC)和中国科学院植物所(PE)中国科学院广西植物所标本馆(IBK).  相似文献   

2.
《技术与市场》2007,(4):28-28
应用中草药预防蛇病虽然刚刚开始,在南方诸省(区)甚至全国各地的蛇场还未得到大面积的推广应用,但只是时间早晚的问题.其实,用中草药预防蛇病是一个全新的概念和途径,是生产绿色食品(蛇肉)的重要手段,也是减少蛇肉、蛇胆等抗生素残留超标的好措施.所以,用中草药预防蛇病是今后的必然趋势.  相似文献   

3.
黑鲍鱼菇是四川农业大学农学院应用微生物系教师采用细胞工程技术选育的食用菌新品种,又名晚生北风菌、冻菌、黑菇、黑鸡菇等,是北风菌中的珍品.其菌盖黑色、菌肉乌黑色、菌褶褐黑色、菌柄乌黑、基部略呈白色,子实体柄短、盖大、肉厚、质嫩,食之鲜香滑嫩、细腻爽口、具鲍鱼鲜味,口感远远超过平菇甚至凤尾菇、香菇等大多数食用菌类,是满足人们对黑色食品强烈需求的高档菇类,深受各地消费者喜爱.黑鲍鱼菇含有18种氨基酸和多种复合型维生素,含有人体必需的8种氨基酸和丰富的多糖体,富含钙、锌、铜、硒等微量元素,对增强人体免疫力、改善肾功能有非常好的作用.目前,该产品供不应求,是能给菇农带来较大经济效益的食用菌新品种.  相似文献   

4.
Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.  相似文献   

5.
BP and RBF neural network to predict forest stock volume were studied,but the study in evaluating both networks’ application effects was not conducted.In order to find a higher forecast precision,more strong applicative method,the comprehensive analysis and evaluation on the two methods were carried out in the practical application. By the correlation analysis,crown density,shady-slope and sunny-slope,TM1,TM2,TM3,TM5, TM7,NDVI,TM,(4-3),TM4/3 were selected as input variables,and the forest volume of Miyun County as output variables,RBF and BP neural network models for forecasting the forest volume were established.And the neural network training step length,training time,prediction accuracy and the applicability model of the two methods were comprehensively analyzed.The results show that the RBF neural network model is superior to the BP neural network model.  相似文献   

6.
Carbon management index(ICM) is used to evaluate the scientificity of soil management.Soil organic carbon(SOC) and readily oxidized carbon (ROC) contents under Leucaena leucocephala stand, Acacia glauca stand,Acacia auriculiformis stand, Azadirachta indica stand,wasteland and dry cropland were determined and their ICM were calculated.The results showed that the SOC and ROC contents under the 6 land use types were 4.22-5.92 g·kg-1 and 1.34-2.33 g·kg-1,respectively.No significant differences in SOC contents among these land uses were observed.The ROC contents under the 4 types of woodland,however,were significantly higher than these under dry cropland or wasteland(P<0.05). The ROC were high significantly(P<0.001) correlated(R2 is 66.3%) with SOC.Compared with wasteland,the ICM ranged from 1.77 to 2.36 under these woodlands,and 0.99 under dry cropland.It is revealed that the litter quantity and land management under these land uses may be the key factors resulting in the variation of ROC.At ecological fragile region of Dry-hot Valley,closure management is useful to sequestrate C in woodland soils.However,the management systems for soil carbon pool under dry cropland are not in a sound way.  相似文献   

7.
The Pine Barrens in New York State are dominated by pitch pine(Pinus ridgida) and scrub oaks(Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become sparse, even in areas set aside to preserve this type of vegetation. We evaluated the effects of fire and an alternative disturbance(mechanical removal of vegetation)for increasing P. rigida regeneration in the Albany Pine Bush Preserve in eastern New York State. By comparing cover, diameter and height of P. rigida, Q. ilicifolia, Q.prinoides, and Vaccinium spp.(blueberry) growing on the sites with a known fire history, we documented structural and compositional changes in the vegetation since its establishment. We also compared sites on which Quercus sprouts were controlled through mechanical removal. In the years following a disturbance, height and cover of Q. ilicifolia increased continuously and the species became increasingly competitive. Both the density of P. rigida seedlings and Vaccinium cover decreased significantly as the diameter and height of Quercus increased. Our results confirmed that the dominance by P. rigida could be attributed to periodic fires at intervals of 20–25 years. We conclude that removing Q. ilicifolia can favor P. rigida dominance on the barren without fire by releasing pine seedlings from competition.  相似文献   

8.
Freezing and thawing indices are not only of great significance for permafrost research but also are important indicators of the effects of climate change.However,to date,research on ground-surface freezing and thawing indices and their relationship with air indices is limited.Based on daily air and ground-surface temperatures collected from 11 meteorological stations in the source region of the Yellow River,the freezing and thawing indices were calculated,and their spatial distribution and trends were analyzed.The air-freezing index(AFI),air-thawing index(ATI),ground surface-freezing index(GFI),ground surface-thawing index(GTI),air thawing-freezing index ratio(Na)and surface ground thawing-freezing index ratio(Ng)were 1554.64,1153.93,1.55,2484.85,850.57℃-days and 3.44,respectively.Altitude affected the spatial distribution of the freezing and thawing indices.As the altitude increased,the freezing indices gradually increased,and the thawing indices and thawing-freezing index ratio decreased.From 1980 to 2014,the AFI and GFI decreased at rates of 8.61 and 11.06℃-days a-1,the ATI and GTI increased at 9.65 and 14.53℃-days a-1,and Na and Ng significantly increased at 0.21 and 0.79 decade-1.Changes in the freezing and thawing indices were associated with increases in the air and ground-surface temperatures.The rates of change of the ground surface freezing and thawing indices were faster than the air ones because the rate of increase of the groundsurface temperature was faster than that of the air and the difference between the ground surface and air increased.The change point of the time series of freezing and thawing indices occurred in 2000–2001.After 2000–2001,the AFI and GFI were lower than before the change point,and the changing trend was lower.The ATI,GTI,Na and Ng during 2001–2014 were higher,with faster rates than before.In addition,the annual thawing indices composed a greater proportion of the mean annual air temperature and mean annual ground surface temperature than the annual freezing indices.This study provides the necessary basis for research on and prediction of permafrost changes,especially changes in the depth of the active permafrost layer,climate change,and possible evolution of the ecological environment over the source region of the Yellow River on the Qinghai-Tibet Plateau.  相似文献   

9.
玉参属一年生或多年生肉质草本植物,直根系,主根圆柱形,肉质表皮棕褐色,是餐馆的高档蔬菜.玉参具有清热解毒、生津止渴、补气血、助消化之功效.对气虚乏力、脾虚泄泻、神经衰弱、肺燥咳嗽有一定疗效.  相似文献   

10.
15年前,青阳县乔木乡项目林场刚栽的国外松小苗星星点点布满在3000多亩荒丘岗上,没有引起多少人注意.如今,小苗长成了参天大树,茂密的森林将这里妆扮成绵延数公里的绿海,引来了一批又一批参观的人群.据介绍,这片林木平均树高已达8米,亩均蓄积量已超过12立方米.这是我省引进世界银行贷款营建的速生丰产林中的一个典型.  相似文献   

11.
通过2002~2004年花卉苗木立枯病的基本调查,初步掌握了大连地区花卉苗木立枯病的发病原因及其发生规律;研究了立枯病的流行动态过程及其影响因素。针对主要侵染性病原和非侵染性病原,提出了具体防治方法。  相似文献   

12.
桑树为桑科桑属植物。我国是桑树的故乡,也是世界上桑叶的主产地之一。桑树在我国已有4 000多年的栽培历史,数千年来,桑树在我国丝绸业的发展过程中起到了决定性的作用。我国桑树资源极为丰富,品种繁多k,主要有:家桑或白桑(Morus alba)、鸡桑(M. australis)、华桑(M. cathayana)、蒙桑(M. mongolic)、山桑(M. diabolica )等10多个种和变种。桑叶有着极高的营养价值和药用价值,成为食品科技界和医药界关注的热点。目前,日本已有部分桑叶保健品面市,并深受消费者的喜爱。随着人民生活水平的不断提高,桑叶制品将越来越得…  相似文献   

13.
在阿伦河上中游典型地段之甘南县山湾村按生态经济学原理构建一个村级规模的流域治理开发模式:人工建造植被67.3hm2,封育天然灌丛60hm2;建造防洪大堤7000延长米,丁坝一座2200延长米,疏通淤积河道5000延长米,并对其将产生的效益进行了分析。结果表明该模式将产生显著的经济、生态、景观效益,对嫩江中上游流域各支流的治理具有重要参考和借鉴作用。  相似文献   

14.
辽宁杨树主要病虫害的识别及防治   总被引:3,自引:0,他引:3  
文章对辽宁省杨树速生丰产林建设发展中经常遇到的病虫害进行了介绍,并重点阐述了发生在杨树上的主要种类蒙古象甲、黑绒金龟、白杨透翅蛾、杨干象、青杨天牛、光肩星天牛、杨树溃疡病、杨树腐烂病、杨树黑斑病的形态识别、危害部位和防治方法等。  相似文献   

15.
广西速丰桉的主要病害8种,害虫11种,发生面积大,病、虫单独或混合发生。病虫害发生的主要原因是大面积种植人工纯林、存在明显的病虫种群优势。病虫害防治应采取生态调控和生物防治。  相似文献   

16.
贵州古树名木保护与管理对策探讨   总被引:3,自引:1,他引:3  
文章从贵州古树名木现状、古树生长发育规律及环境条件对古树影响出发,分析古树名木衰老原因及其复壮的理论基础,提出了贵州古树名木保护、管理的措施和建议。  相似文献   

17.
"无刺丰"与"深秋红"沙棘品种的选育及其特征   总被引:2,自引:0,他引:2  
黄铨  赵勇 《沙棘》2004,17(4):7-9
1990年从芬兰和俄罗斯引入沙棘优树或品种沙棘种子45份,于1991年在阜新县育苗,1992年造林,1995年和1999年在阜新市郊区经两次易地移栽,2001年取其分生株,植于内蒙古库伦,经14年的多次被动迁移过程,最终以实生选种法选育出两个沙棘无性系品种。“无刺丰”全株无刺,树冠披散形,采果容易,单株产果量可达20kg,宜作经济型林木栽培。“深秋红”为无刺或少刺的主干型灌木或亚乔木,果实密集、色红、鲜亮,并经冬不落,为我国北方理想的秋冬景观型品种。  相似文献   

18.
旅游业的发展与相应法律法规的完善   总被引:1,自引:0,他引:1  
武术杰 《吉林林业科技》2000,29(6):34-35,44
本文从旅游资源环境、旅游企业经营、旅游者合法权益保护方面对旅游业存在的问题及现有法律、法规的不足进行了分析,并指出针对旅游现状应制定相应的法律规范,以保证旅游业的健康顺利发展。  相似文献   

19.
云杉引种及种和种源早期评价   总被引:2,自引:1,他引:1       下载免费PDF全文
对引进的欧洲云杉、西加云杉、白云杉、黑云杉以及国内的川西云杉和青海云杉的24个不同种和种源生长及分枝性状进行早期(8年生)测定与评价.结果表明:5年生长期内生长及形态性状在不同的云杉种间和种源间的差异多数达到极显著或显著水平,且种和种源的方差分量分别占总方差分量的32.47%和23.97%,证明不同种间和种源间存在较大的遗传变异.通过多重比较和相关分析发现,国外的云杉种较国内种在生长表现和适应性上均有明显的优势.经性状相关分析得知:各个生长及形态性状之间均存在极显著的正相关关系,尤其是苗高与各分枝性状之间的相关系数均值为0.825 9.最后利用苗高为主要指标初步筛选出6个优良种源,人选的种源均表现出明显的优势,其中苗高、侧枝总数以及当年侧枝数的平均值分别为117.07 cm、57.75、12.46,均分别比对照种源的总平均值高48.54%、56.46%和63.30%.  相似文献   

20.
通过研究分析表明:兰州市园林绿化用土紧缺,绿地土壤存在密实度高、有机质含量低、污染严重、土源短缺、养护管理缺乏科学性等问题,必须提高土壤改良的科学性和管理的有效性,确保兰州市园林绿化事业的可持续发展。  相似文献   

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