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1.
一个简易装置验证叶的"三大"功能龙跃飞(江苏省射阳县城东中学224300)叶是植物体一个十分重要的营养器官。光合作用、呼吸作用、蒸腾作用是叶的"三大"功能。这"三大"功能在初中生物学乃至高中生物学都是一个极其重要的内容。而以往的教参或教科书都是将这"...  相似文献   

2.
由中国科学院微生物研究所,安徽省医学科学研究所,江苏省无锡酶制剂厂,江苏省射阳制药厂共同协作研制的药用中性蛋白酶的中试鉴定会,于1979年8月15日至18日,在江苏射阳召开。会议由江  相似文献   

3.
棉纤维发育过程中基因表达的研究进展   总被引:3,自引:0,他引:3  
陈松  吴敬音 《生物学杂志》1998,15(1):5-7,12
棉纤维发育过程中基因表达的研究进展陈松周宝良(江苏省农业科学院经济作物研究所,南京210014)吴敬音(江苏省农业科学研究院生物遗传生理研究所,南京210014)前言棉纤维是由胚珠表皮细胞经过分化、伸长、次生壁加厚等一系列过程发育形成的,其发育过程...  相似文献   

4.
3种中药前胡的氢谱鉴定和化学分类叶锦生,吴美玉,刘启新(江苏省植物研究所,中国科学院植物研究所,南京210014)(江苏省化工研究所,南京210024)Identificationandchemotaxonomyof3Chinesecrudedrug...  相似文献   

5.
悬钩子属3个种粗制备物糖成分的差异宋长铣王传永李维林顾姻(江苏省中国科学院植物研究所,南京210014)供试材料系南京中山植物园生长的山莓(RubuscorchorifoliuL.f)、蓬(R.hirsutusThunb.)和高粱泡(R.lamber...  相似文献   

6.
关于调整竹林生态系统食物链的研究   总被引:1,自引:0,他引:1  
关于调整竹林生态系统食物链的研究李昌荣,屠六邦,吴继林(南京林业大学,210037)(福建省永安市大湖林业站,366015)王进荣,黄文培(江苏省溧水县秋湖林场,211200)(四川省长宁万岭楠竹研究所,644304)StudyonRegulatin...  相似文献   

7.
猪基因定位研究进展丁岳明,陈宜峰(南京师范大学生物系南京210024)朱洪生(江苏省农林厅南京210009)一、前言对家猪(SussorofaL。)的基因定位工作可以追溯到本世纪六十年代。1964年,Andresen等[1]首次报道了猪的红细胞抗原C基因(EAC)和J基因(EAJ)存在连锁关系。但早期的工作由于方法的限制,一直进展缓慢。  相似文献   

8.
水稻体细胞培养中胚性细胞出现与IAA的关系   总被引:21,自引:0,他引:21  
水稻体细胞培养中胚性细胞出现与IAA的关系陈以峰1周燮2汤日圣2张金渝2梅传生1(南京农业大学农学系南京210095)2(江苏省农业科学院农业生物遗传生理研究所南京210014)关键词水稻,胚性细胞,IAA,2,4二氯苯氧乙酸,2,3,5三碘...  相似文献   

9.
苯酚在蚕桑生态系统中的积累和迁移潘如圭,吴长年,陈为民,管竟芳,王静江,陈德梅(江苏省植物研究所南京210014)(江苏省浒墅关蚕种场)AccumnulationaudMigrationofPhenolinSericulturalEcosystem....  相似文献   

10.
何继龙  储西平 《昆虫学报》1996,39(3):312-316
中国食蚜蝇属一新种记述(双翅目:食蚜蝇科)何继龙,储西平(上海农学院园林环境科学系上海201101)(江苏省农业科学院植物保护研究所南京210014)食蚜蝇属Syphus是Fabricius建立于1775年。此时的食蚜蝇属Syrphus(s.1.)是...  相似文献   

11.
为了研究不同植被覆盖度、不同林相及不同林种林下土壤水源涵养的特性,以浙江省苕溪流域上游区为例,采用野外不同林种土壤持水能力定时定点实测取样、室内不同植被覆盖度(0,15%,30%,45%,60%,75%,90%)、不同林相(上层覆盖、下层覆盖、上下层覆盖)的物理模型人工模拟降雨试验方法,通过不同深度土壤水分含量测试、产汇流和入渗系数计算,探索了林地不同经营管理方式下土壤涵养水源的特性,结果表明:(1)地表入渗系数随植被覆盖度的增加而增大,随坡长增加入渗系数的增长比率增加,降雨过程中植被覆盖度对入渗系数的影响比坡长的影响大。(2)不同林相的模拟试验结果表明,地表入渗系数排序为上下层覆盖上层覆盖下层覆盖裸地。随着产流历时增加,林下土层的蓄水量呈线型增加,与裸坡比较,累积蓄水量增加百分数为:上层覆盖为23%,下层覆盖为29%,上下层覆盖为37%。(3)通过监测不同林地不同深度土壤含水率的变化,并与裸地进行对比得出不同林地涵养水源能力的强弱。其蓄水能力排序分别为板栗林茶园竹林。研究结果为林地管理、林相培育和林下土壤持水能力的提高具有科学方法论上的支撑和生产实践方面的借鉴。  相似文献   

12.
Aims Government policy in Ireland is to increase the national forest cover from the current 10% to 18% of the total land area by 2020. This represents a major land use change that is expected to impact on the national carbon (C) stocks. While the C stocks of ecosystem biomass and soils of Irish grasslands and coniferous forests have been quantified, little work has been done to assess the impact of broadleaf afforestation on C stocks.Methods In this study, we sampled a chronosequence of ash (Fraxinus excelsior) forests aged 12, 20, 27, 40 and 47 years on brown earth soils. A grassland site, representative of the pre-afforestation land use, was sampled as a control.Important findings Our results show that there was a significant decline (P < 0.05) in the carbon density of the soil (0–30cm) following afforestation from the grassland (90.2 Mg C ha-1) to the 27-year-old forest (66.7 Mg C ha-1). Subsequently, the forest soils switched from being a C source to a C sink and began to sequester C to 71.3 Mg C ha-1 at the 47-year-old forest. We found the amount of C stored in the above- and belowground biomass increased with age of the forest stands and offset the amount of C lost from the soil. The amount of C stored in the above- and belowground biomass increased on average by 1.83 Mg C ha-1 year-1. The increased storage of C in the biomass led to an increase in the total ecosystem C, from 90.2 Mg C ha-1 at the grassland site to 162.6 Mg C ha-1 at the 47-year-old forest. On a national scale, projected rates of ash afforestation to the year 2020 may cause a loss of 290 752 Mg C from the soil compared to 2 525 936 Mg C sequestered into the tree biomass. The effects of harvesting and reforestation may further modify the development of ecosystem C stocks over an entire ash rotation.  相似文献   

13.
永定河流域官厅水库南岸典型林分土壤饱和导水率研究   总被引:6,自引:0,他引:6  
为研究永定河流域官厅水库南岸生态水源保护林土壤饱和导水率(K_(fs))的特征,科学评价水源保护林功能,选取水源保护林典型林分与当地成林和非林地作对比,采用方差分析、相关分析和因子分析的方法研究土壤理化性质对饱和导水率的影响并根据因子得分排名探究土壤通透性最好的林分。结果表明:(1)土壤饱和导水率随土层深度增加而减小,水源保护林中混交林的饱和导水率大于纯林接近于成林,侧柏×山杏混交林的饱和导水率最高;(2)因子分析结果表明,影响饱和导水率最主要的因素为饱和含水量、容重和有机质含量;次重要因子为土壤砂粒、粉粒和粘粒含量,土壤毛管孔隙度和非毛管孔隙度对本区域饱和导水率影响不大;(3)综合因子得分排名分析,以侧柏×山杏混交林的土壤通透性最好,油松×山杏混交林次之。目前生态水源保护林对土壤通透性的改善优势明显,造林颇具成效。  相似文献   

14.
赵旭  樊军  付威 《应用生态学报》2020,31(5):1599-1606
土壤侵蚀是东北黑土退化的主要原因之一,了解不同土地利用方式下土壤水气传输性质的差异,可以为黑土区水土资源的高效利用和保护提供科学依据。本研究选取东北黑土区典型的3种土地利用方式(农地、林地、撂荒地)进行0~5 cm土层原位土壤饱和导水率、导气率和相对气体扩散率的测定,探讨土壤侵蚀和土地利用方式对土壤水气传输性质的影响。结果表明:不同侵蚀程度农地之间以及不同土地利用方式之间土壤水气传输性质差异显著。重度侵蚀农地容重显著高于其他样地,未侵蚀农地容重显著低于其他样地。与未侵蚀农地相比,轻度、中度和重度侵蚀农地容重分别增加12.7%、17.6%和39.2%,饱和导水率分别降低84.4%、53.7%和12.7%,导气率分别降低94.6%、64.4%和14.0%,相对气体扩散率分别降低91.3%、82.6%和4.3%。松林地饱和导水率、导气率和相对气体扩散率较未侵蚀农地分别降低86.5%、83.0%和91.3%。沙棘林地饱和导水率、导气率和相对气体扩散率较未侵蚀农地分别降低51.7%、45.6%和82.6%,撂荒地饱和导水率、导气率和相对气体扩散率较未侵蚀农地分别降低16.2%、1.4%和73.9%。可以利用测得的土壤导气率、相对气体扩散率估算土壤饱和导水率。土壤侵蚀和土地利用方式显著影响黑土地土壤水气传输特性。  相似文献   

15.
滇中常绿阔叶林及云南松林水文作用的初步研究   总被引:12,自引:1,他引:11       下载免费PDF全文
 本文研究了滇中地区山地常绿阔叶林及云南松林的林冠截留量,冠流和茎流量,地表水土流失量,林地枯枝落叶层持水量,土壤含水量以及雨水、冠流、茎流和地表迳流中营养元素(N、P、K、Ca和Mg)的含量,并分析比较了针、阔两类森林调节和涵养水分的作用和降水中林冠养分的淋溶、迁移特点,对了解滇中亚热带山地森林生态系统的功能和生产力的研究,对本区森林资源的保护,林业的合理经营,均有重要意义。  相似文献   

16.
This study investigated the effects of widespread forest clearance and fragmentation on forest compositional change between pre-settlement and the present (ca. 1800–1993) in western New York. Forest compositional turnover metrics were calculated to evaluate whether soil conditions accounted for the forest compositional change, to investigate how forest clearance might have contributed to the change, and to compare with the amount of change noted in other studies that compared the pre-settlement land surveys and the current Forest Inventory and Analysis (FIA) surveys. The results suggested weak relations between the forest compositional change and soil conditions. The amount of change at the county level was positively correlated with the amount of forest clearance by the late 1800s and negatively correlated with the amount of remnant forest in the late 1800s. Furthermore, while the geographic distributions of late-successional taxa in the study area exhibited increased patchiness and decreased contagion, those of early-successional taxa exhibited decreased patchiness and increased contagion. Comparison of taxa’s changed abundances with seven life history characteristics commonly associated with early- and late-successional status showed that taxa’s changed abundances were significantly related to maximum life and shade tolerance. Analysis of different-sized trees in different ages in the FIA survey indicated the possibility of the current forests trending back toward their pre-settlement composition.  相似文献   

17.
土壤有机质分解是陆地生态系统碳循环的重要环节,它不仅受温度和水分的影响,还对土地利用变化十分敏感.以中国科学院千烟洲生态试验站的柑橘园和湿地松人工林为对象,研究不同土地利用类型、温度(5、10、15、20和25 ℃)和水分(30%、60%和90%饱和含水量)对土壤碳矿化及其温度敏感性的影响.结果表明: 土地利用类型、温度和水分对土壤碳矿化都具有显著影响,且各因素间存在显著的交互效应.柑橘园和湿地松人工林土壤碳矿化速率均与温度呈正相关,60%饱和含水量处理下土壤碳矿化速率最高.在相同的温度和水分处理下,柑橘园土壤碳矿化量显著高于湿地松林.土地利用类型和水分对土壤碳矿化温度敏感性(Q10)具有显著影响.培养7和42 d,土壤碳矿化的温度敏感性随水分升高而上升;柑橘园温度敏感性高于湿地松林,且水分越高差异越明显.包含温度和水分的双因素模型可以很好地模拟土壤碳矿化对温度和水分的响应,温度和水分共同解释土壤碳矿化变异的79.9%~91.9%.  相似文献   

18.
热带地区的降水时间集中,降水强度大,一旦森林破坏地表裸露后,很容易引起生态性危害,山地尤甚。本文通过观测和对比试验,初步探讨了海南岛尖峰岭半落叶季雨林的生态效益及流动农业所造成的生态恶果。毁林耕垦当年即可使地区性小气候恶化、水土流失严重、地力开始减退。  相似文献   

19.
林莎  王莉  李远航  陈梦飞  贺康宁 《生态学报》2019,39(18):6610-6621
为探讨青藏高原东北缘黄土区典型立地人工林分的土壤水分特性及耗水特性,本研究以青海云杉林地和祁连圆柏林地作为研究对象,对其土壤持水特性、土壤渗透特性、土壤水分动态和土壤耗水特性进行综合分析。研究结果表明:(1)在相同土壤水吸力作用下,青海云杉林地的持水性比祁连圆柏好,荒草地的持水性比林地差。(2)青海云杉林地的土壤渗透性总体优于祁连圆柏,荒草地的土壤渗透性最差。相同坡向,上坡位的土壤渗透性小于下坡位。(3)青海云杉林地土壤水分条件总体优于祁连圆柏,而荒草地土壤水分条件优于林地;半阴坡林地土壤含水量随坡位由上至下逐渐升高。(4)生长季期间,青海云杉林地平均耗水量大于祁连圆柏,而荒草地耗水量远小于林地。综上,青海云杉林地的土壤水分特性整体优于祁连圆柏林地,且二者的土壤水分状况都比较好,并未出现土壤干层、土壤水分过度消耗等现象,青海云杉和祁连圆柏在研究区的配置是合理的,可以作为当地的水源涵养树种。  相似文献   

20.
For confidently estimating the amount of carbon stored in boreal forestsoil, better knowledge of smaller regions is needed. In order to estimatethe amount of soil C in forests on mineral soil in Finland, i.e. excludingpeatland forests, and illustrate the regional patterns of the storage,statistical models were first made for the C densities of the organic and0–1 m mineral soil layers. A forest type, which indicated siteproductivity, and the effective temperature sum were used asexplanatory variables of the models. In addition, a constant C densitywas applied for the soil layer below the depth of 1 m on sortedsediments. Using these models the C densities were calculated for atotal of 46673 sites of the National Forest Inventory (NFI). The amountof the soil C was then calculated in two ways: 1) weighting the Cdensities of the NFI sites by the land area represented by these sites and2) interpolating the C densities of the NFI sites for 4 ha blocks to coverthe whole land area of Finland and summing up the blocks on forestedmineral soil. The soil C storage totalled 1109 Tg and 1315 Tg, whencalculated by the areal weighting and the interpolated blocks,respectively. Of that storage, 28% was in the organic layer, 68% inthe 0–1 m mineral soil layer and 4% in the layer below 1 m. The totalsoil C equals more than two times the amount of C in tree biomass and20% of the amount of C in peat in Finland. Soil C maps made usingthe interpolated blocks indicated that the largest soil C reserves arelocated in central parts of southern Finland. The C storage of theorganic layer was assessed to be overestimated at largest by 13% andthat of the 0–1 m mineral soil layer by 29%. The largest error in theorganic layer estimate is associated with the effects of forest harvestingand in the mineral soil estimate with the stone content of the soil.  相似文献   

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