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1.
通过对比外源激素提高杜仲短周期矮林地上部分生物量和杜仲胶产量的效果,筛选出合适的外源激素种类及其田间施用质量浓度,为杜仲胶资源林培育提供技术支撑。以1年生栽植密度为66 666株·hm~(-2)的杜仲短周期密植矮林为对象,采用芸苔素内酯和赤霉素2种外源激素,按完全随机区组设计,通过比较杜仲叶和皮内杜仲胶含量的变化,苗木生长特性以及叶、皮、茎秆等地上部分生物量指标,分析施用外源激素对杜仲胶产量产生的作用效果。结果表明:(1)赤霉素显著促进苗高生长,但对其它指标的增效作用不明显。(2)经质量浓度为1 mg·L~(-1)和5 mg·L~(-1)的芸苔素内酯处理后,杜仲叶片内杜仲胶含量达到了4.74%、5.01%,分别是对照的3.21和3.04倍;苗高分别较对照增加了12.26%和16.09%;平均单株叶片数分别均比对照多8片;单株叶片质量分别是对照的2.21和2.25倍;单株树皮质量分别是对照的1.97和2.05倍;叶片生物量为2 993.54和3 089.83 kg·hm~(-2),树皮生物量为576.87和543.78 kg·hm~(-2),茎杆生物量为2 060.71和1 935.24 kg·hm~(-2),分别是对照的2.16和2.23倍、2.00和1.89倍、2.07和1.94倍。按平均含胶量计算,单位面积杜仲胶产量分别达到了167.28和182.90 kg·hm~(-2),分别为对照的4.58和5.01倍。(3)芸苔素内酯通过提高叶片胶含量、苗高生长量、单株叶片数、单株叶、皮、杆干质量等综合效应,在第一个采伐期即表现出极显著提高高密度杜仲矮林生物量和杜仲胶产量的效果。  相似文献   

2.
以黄檗3 a生幼树为材料,对不同栽植密度的生物量进行研究,结果表明:栽植当年和翌年秋季的成活率与保存率分别为92%和91%。不同株距树高、地径生长量均达到极显著差异(P0.01),树高、地径生长量从大到小顺序依次为株距0.5 m1 m0.3 m1.5 m;而不同行距对树高、地径生长量均无影响。采用一元生物量模型计算生物量,总生物量最大的种植密度为33 300株·hm~(-2)(株行距0.3 m×1.0 m),可产生干物质3 930.06 kg·hm~(-2);最小的为3 300株·hm~(-2)(株行距1.5 m×2.0 m),干物质仅为344.08 kg·hm~(-2)。  相似文献   

3.
为探索果园化栽培杜仲幼林的生产力水平,创新平原沙区困难立地条件杜仲人工林培育模式,基于4 a连续实测数据测算出平原沙区杜仲果园的生物量及相关计量参数。研究结果表明:果园化栽培模式下建园第1年、第2年、第3年、第4年杜仲林生物量迅速增加,分别达0.762±0.117 t·hm-2、2.576±0.291 t·hm-2、8.717±0.762 t·hm-2和13.003±1.555 t·hm-2;枝叶比以建园第3年的杜仲林最高,达1.457,枝叶指数以建园第4年杜仲林最高,达0.719;建园1~4 a杜仲果园冠根比差异较大,在1.866~3.985之间波动;非光合部分生物量与光合部分生物量比值在1.790~3.916之间;建园第4年杜仲生物量最高,地径、树高、树干中间直径及冠幅平均值分别达6.83±0.74 cm、2.53±0.21 m、5.78±0.80 cm和1.81±0.11m,其生产力水平可达3.26 t·hm-2a-1。果园化栽培模式可作为平原沙区困难立地条件杜仲人工林的重要栽培模式之一,建议在生产上应用。  相似文献   

4.
中亚热带人工米槠林分生产力   总被引:1,自引:0,他引:1  
在福建省沙县官庄国有林场,以同年度、相似立地条件下的人促米槠林和杉木林为对照,从林分生长、生物量及其分配和空间格局、净生产量、叶净同化率等方面,对17年生人工米槠林的林分生产力进行研究。结果表明:现存密度875株·hm~(-2)的人工米槠林,平均胸径25.7 cm,平均树高14.5 m,单株立木材积0.3534 m3·株-1,林分立木材积309.225m3·hm~(-2),平均木生物量148.06 kg·株-1,年净生长量8.71 kg·株-1·a-1,叶对树干净同化率达115.55 g·m-2·a-1,树冠生长发育较完整,单木生长量、生物量均高于人促米槠林和杉木林,具有较高的生产力。以培育优质大径材为目的的人工米槠林现存密度875株·hm~(-2)是适宜的,有利于培育大径材。  相似文献   

5.
对建瓯市房道镇境内30hm~2Ⅱ类地上16年生人促闽粤栲林分调查结果表明,林分生物量(地上部分)159.22t/hm~2,其中乔木层生物量155.32t/hm~2;林分年均净生长量10.59t/(hm~2·a),其中乔木层年均净生长量9.71t/(hm~2·a);林分平均胸径13.6cm,平均树高14.6m,平均密度2483株/hm~2,平均蓄积量269.0m~3/hm~2,平均蓄积生长量16.8m~3/(hm~2·a);林分叶面积指数4.771m~2/m~2,叶对树干净同化率166.8g/(m~2·a)。  相似文献   

6.
采用常规的标准地调查方法、树干解析方法对福建省光泽县司前乡举安村苦槠次生林的生长规律与生物量进行研究。结果表明:苦槠次生林乔木层有35个树种,苦槠平均木年龄为40 a,密度(310株·hm~(-2))仅占乔木层总株数的25%,但蓄积量占总蓄积量(141.97 m~3·hm~(-2))的69.52%,居优势地位;苦槠的侧根发达,细根较少,早期生长缓慢,树高连年生长量、平均生长量最大峰值分别是第13年、第17年;胸径连年生长量、平均生长量最大峰值分别是第9年、第24年;苦槠的平均木单株材积(去皮)连年生长量、平均生长量在40 a中均处于上升趋势,但连年生长量少数年份有波动,于第37年出现最大值(0.018 24 m~3·a~(-1)),两曲线未相交且相距较远,表明单株材积未达到数量成熟年龄。苦槠次生林乔木层密度为1240株·hm~(-2),总生物量约为141.54 t·hm~(-2);40年生苦槠次生林单株生物量为317.39 kg·株-1,各器官的生物量大小顺序为:树干(去皮)>枝>根>皮>叶。  相似文献   

7.
【目的】了解杜仲短周期矮林模式适宜的收获时间和种植密度。【方法】在66 667株/hm~2栽植密度下,按完全随机区组试验设计,设定4个收获时间,分别为2017年8月30日、9月15日、9月30日和10月15日,每个时间点收获时分成2组,一组平茬后将根桩覆土,另一组不覆土,于次年观察发芽时间,测定生长指标和生物量,比较66 667、33 333、22 222、16 667和13 333株/hm~2种植密度下杜仲矮林地上部分生物量。【结果】收获时间影响次年杜仲的发芽时间,总体上收割越早,发芽越晚。对收割后根桩进行覆土,次年不同收获时间叶片、树皮和茎各自处理间的生物量差异均显著。其中,2017年9月30日和10月15日收割的矮林,次年叶片、树皮和茎的生物量较其他处理高;平茬后根桩未覆土组中,次年不同收获时间叶片、树皮和茎各自处理间的生物量差异均不显著,而且各器官未覆土组生物量大多高于覆土组。另外,33 333和66 667株/hm~2栽植密度下的叶片、树皮和茎生物量显著高于其他3个栽植密度的生物量,其中33 333株/hm~2栽植密度下叶片、树皮和茎的生物量均值分别为4 656.71、1 967.28和15 121.02 kg/hm~2。【结论】应尽量待杜仲短周期矮林苗木进入休眠期进行收割,及时进行平茬后根桩的覆土作业,栽植密度最好采用33 333株/hm~2,每个根桩留置2~3个主枝,有利于次年生物量的积累。  相似文献   

8.
为了解红锥人工林的生物量特征,采用径阶标准木收获法建立相对生长方程,对桂东南12年生红锥人工林的生物量及其分布特征进行了研究。结果表明:红锥人工林乔木层生物量为31.38±1.93 t·hm~(-2),净生产量为2.62±0.24 t·hm~(-2)a~(-1);生物量在各器官的分配为干(53.85%)根(28.30%)枝(10.57%)皮(6.32%)叶(0.95%),干、根为主要分配器官,两者占总生物量的82.15%;沿树干向上,干、皮生物量逐渐减少,而活枝和叶生物量则呈先增后减少的趋势,活枝、叶生物量在树干高度4~6 m段达到最大;根系生物量以根桩所占的比例最高,细根最小。  相似文献   

9.
通过对4个柳树品种不同密度、不同采伐年限的萌条数、含水量、生长量以及生物量的调查测量与研究比较,得出各品种的含水量是品种特性,受密度、生长年份和生长年限的影响较小;同时还得出密度和轮伐期对不同类型柳树生物量的影响规律:在较短的轮伐期设置下,适当延长采伐年限有利于生物量的生产;在1万~3万株/hm~2密度设置下,灌木柳的生物量明显优于乔木柳;灌木柳在高密度设置下生物量相对较大,对乔木柳来说,在较短年限的采伐模式下,较高的造林密度能明显提高生物量,而过高的密度在多年生的情况下达不到高产的目的;比较4个柳树品种不同密度3个采伐年限生物量,杞柳以3万株/hm~2密度设置、2年一采伐为最佳配置模式,其年均生产生物量干质量为11.72 t/hm~2。  相似文献   

10.
根据湖南会同生态定位站11a 定位实测数据,对二代杉木人工林生物量及其垂直分布进行了研究,结果表明:密度为2175株·hm~(-2)的第二代11a 生杉木林乔木层的生物量为74.76t·hm~(-2),净生产力为6.80t·hm~(-2)·a~(-1)。其生物量分布格局为树干>树叶>树枝>树皮;在林分产量方面6m 以下树干占其总产量的82%,叶、枝主要分布在5~9m,叶占其总量的78%,枝占其总量的74%,根生物量主要集中在地表土壤30cm 以内,占其总量的89%。  相似文献   

11.
对广西宁明县相似立地条件下1年生尾巨桉(DH32-29)和雷林1号桉幼林的生物量和5种营养元素(N、P、K、Ca 和 Mg)积累量及其分配特征进行了研究。结果表明:1年生尾巨桉和雷林1号人工幼林林分生物量分别为13.70和12.06 t·hm–2,不同器官生物量均以树干最大,树叶或树根最小。两种桉树不同器官中营养元素含量均以树叶最高,其次是树皮、树枝和树根,树干最低,林木不同器官中营养元素含量均以 N 最高,其次是 K 和 Ca,Mg 和 P最低。1年生尾巨桉幼林营养元素积累量为124.84 kg·hm–2,略低于雷林1号桉幼林(132.76 kg·hm–2),5种营养元素积累量在尾巨桉人工林的分配为树叶>树枝>干皮>干材>树根,在雷林1号桉的分配为树枝>树叶>干材>干皮>树根。尾巨桉幼林营养元素利用效率略高于雷林1号桉幼林。  相似文献   

12.
通过对叶林模式杜仲6—10月的生物量动态变化的调查分析,结果表明:杜仲枝条长度和粗度前期增长较快,而到8、9月以后,增长缓慢,在10月份达到最大值,分别为115.57 cm和1.971 cm。6—8月为杜仲枝条皮干重的缓慢增长期,8—10月为杜仲枝条皮干重的快速增长期,在10月份最高,达到15.99 g;不同月份杜仲枝条皮含水率从高到低顺序为:6月>8月>9月>7月>10月,6月份最高可达74.7%,而10月份最低为68.88%。6—7月杜仲剥皮枝条干重增长不明显,7—10月为杜仲剥皮枝条干重的快速增长期,在10月份最高,达到111.63 g。不同月份杜仲剥皮枝条含水率从高到低顺序为:6月>7月>8月>9月>10月,6月份最高可达66.95%,而10月份最低为50.16%。6—9月为杜仲叶(单枝)总干重的增长期,9—10月为稳定期,9月份最高,达到48.96 g;不同月份杜仲叶(单枝)含水率从高到低顺序为:9月>8月>6月>10月>7月,9月份最高可达72.44%,而7月份最低为69.91%。不同月份杜仲叶片数量(单枝)从多到少顺序为:8月>9月>10月>7月>6月,8月份最多可达59片,而6月份最少为39.7片。建议以杜仲叶子为原料的加工产业,应在9月采摘叶子。  相似文献   

13.
Palmatine is a valuable ingredient in Chinese medicine that is produced by Phellodendron amurense Rupr.The contents of palmatine content in root bark, trunk bark,perennial branch bark, annual branches, and leaves of the trees with different ages and geographies in Northeast China were measured by high-performance liquid chromatography.The contents of palmatine in the barks of root, trunk, and perennial branch were significantly higher than those in annual branches and leaves. The contents of palmatine in trunk bark and root bark from Lesser Khingan Mountains increased with age, which is significantly opposite to other three vegetation types. The contents of palmatine in perennial branch bark, annual bark and leaves had no significant regularity. Moreover, the contents of palmatine in samples of root bark, trunk bark, perennial branch bark and annual bark varied significantly with latitude. The nature populations of P. amurense growing at low latitude contained significantly more palmatine than those growing at high latitude. These results provide a scientific basis for the reasonable cultivation and efficient utilization of P. amurense.  相似文献   

14.
Palmatine is a valuable ingredient in Chinese medicine that is produced by Phellodendron amurense Rupr. The contents of palmatine content in root bark, trunk bark, perennial branch bark, annual branches, and leaves of the trees with different ages and geographies in Northeast China were measured by high-performance liquid chromatography. The contents of palmatine in the barks of root, trunk, and perennial branch were significantly higher than those in annual branches and leaves. The contents of palmatine in trunk bark and root bark from Lesser Khingan Mountains increased with age, which is significantly opposite to other three vegetation types. The contents of palmatine in perennial branch bark, annual bark and leaves had no significant regularity. Moreover, the contents of palmatine in samples of root bark, trunk bark, perennial branch bark and annual bark varied significantly with latitude. The nature populations of P. amurense growing at low latitude contained significantly more palmatine than those growing at high latitude. These results provide a scientific basis for the reasonable cultivation and efficient utilization of P. amurense.  相似文献   

15.
Phellodendron amurense Rupr. produces berberine, a valuable ingredient in Chinese medicine. We examined how berberine content varied in different parts of the tree with age and geography in Northeast China. Berberine levels in root bark, trunk bark, and perennial branch bark, annual branches, and leaves were estimated by high-performance liquid chromatography. Root, trunk, and perennial branch barks had significantly higher berberine content than annual branches and leaves. Moreover, berberine content varied significantly with both longitude and latitude in samples of these three plant parts. The populations growing at low longitude and latitude contained significantly more berberine than those growing at high longitude and latitude. These results provide a scientific basis for the reasonable cultivation and efficient use of P. amurense.  相似文献   

16.
对巴西米纳斯吉拉斯州北部半干旱地区(15°09’S43°49’W)的赤桉(Eucalyptus camaldulensis)和大桉(Eucalyptus grandis)人工林的地上生物量、营养成分含量和菌根菌定植百分率进行了调查和分析。结果表明,赤按和大桉人工林的总地上生物量分别为33.6Mg·hm-2和153.1Mg·hm-2。赤桉树干、叶子、枝条和树皮的生物量分别占总生物量的64.4%,19.6%,15.4%,0.6%,大桉地上生物量的分配与赤按基本相同。赤桉叶子和枝条的干物质占其总生物量的35%,叶子和枝条中的N,P,K,Ca,Mg,and S的含量分别占总生物量这些营养元素的15.5%,0.7%,12.3%,22.6%,19%,1.4%。树干(包括树皮)中的营养成分累积相对比较低。与赤桉相比,大桉的营养含量变化较小。这2个树种的树干上部含有高浓度的磷,树皮也含有大量的营养物质,尤其是大桉;说明在半干旱地区,立地上脱落的植物性废物对降低树木生产力损失有重要意义。赤桉和大桉都有菌根营养。  相似文献   

17.
云南省云杉立木生物量模型研建   总被引:2,自引:0,他引:2  
以云南云杉为研究对象,对云杉地上生物量和地下生物量模型进行研建。建立云杉地上总生物量、树干、树冠、干材、干皮、树枝、树叶独立模型与材积相容模型,采用分级联合控制和度量误差模型方法,建立地上总生物量和所有分量相容的立木生物量模型,建立根茎比模型对云杉地下生物量进行估计。结果表明:建立的云杉地上总生物量、树干、干材生物量二元模型预估精度均达95%以上,干皮生物量模型预估精度达94%以上,树冠、树叶、树枝生物量的预估精度均在92%以上,地下生物量模型预估精度在88%以上;所建立的模型可以用于云杉生物量的估计。  相似文献   

18.
Cultivation of bay leaves (Cinnamomum tamalaNees & Eberm) to fulfil household income needs is a long established practice in Udayapur district of Nepal. The practices adopted by farmers for bay leaf harvesting have not, however, been validated by scientific investigation for their sustainability. To investigate the impacts of harvesting on the yield of branch, leaves and biomass of leaves, a two-year research project was conducted in farm fields at Kopche village of Routa VDC in Udayapur district, Nepal. Four different harvesting treatments, the orien-tation and the order of branches were taken as independent variables to test their effects on number of branches, leaves and biomass of leaves. Orientation, harvesting treatments and order of branches had a significant effect on the number of branches, but not on the number of leaves or biomass (fresh and dry weight) of leaves in the year of harvest. Between two consecutive harvests there was no significant difference in the num-ber of branches, leaves or biomass. Lower two-thirds portion of the trees produced the largest number of leaves and branches of the fourth order in both years. Therefore, lower two-thirds portion of the trees were suitable for harvesting. Our findings support farmer experience that no change in productivity of leaves is observed when harvesting each year. For long term sustainability, harvesting should be conducted without debarking of trees or damage to branches. Our findings could be extrapolated to and tested in other areas with different access and user rights where the rota-tion for harvest is fixed or regulated without research evidence.  相似文献   

19.
A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization in Eucalyptus camaldulensis and Eucalyptus grandis plantations in the semiarid region (15° 09′ S 43° 49′ W) in the north of the State of Minas Gerais in Brazil. Results show that the total above-ground biomass (dry matter) was 33.6 Mg·ha−1 for E. camaldulensis and 53.1 Mg·ha−1 for E. grandis. The biomass of the stem wood, leaves, branches, and stem bark for E. camaldulensis accounted for 64.4%, 19.6%, 15.4%, and 0.6% of the total biomass, respectively (Table 2); meanwhile a similar partition of the total above-ground biomass was also found for E. grandis. The dry matter of leaves and branches of E. camaldulensis accounted for 35% of total biomass, and the contents of N, P, K, Ca, Mg, and S in leaves and branches accounted for 15.5%, 0.7%, 12.3%, 22.6%, 1.9%, and 1.4% of those in total above-ground biomass, respectively. In the trunk (bark and wood), nutrient accumulation in general was lower. Nutrient content of E. grandis presented little variation compared with that of E. camaldulensis. Wood localized in superior parts of trunk presented a higher concentration of P and bark contained significant amounts of nutrients, especially in E. grandis. This indicated that leaving vegetal waste is of importance on the site in reducing the loss of tree productivity in this semi-arid region. The two species showed mycotrophy.  相似文献   

20.
In northern Laos, shortened fallows in the slash-and-burn upland rice system are not sustainable either from a production or economic standpoint. This paper evaluates the potential for using the indigenous fast-growing tree, Broussonetia papyrifera L. Vent. (paper mulberry) as an economic fallow crop. The objectives of this study are to assess the inner bark yield of paper mulberry, and to evaluate rice productivity following paper mulberry cultivation. In addition, allometric models for estimating the inner bark yield of paper mulberry are developed. Inner bark yield of paper mulberry stands ranging in age from 9 to 48 months ranged from 10 to 208 g m−2, and increased with age. The models using diameter at breast height and stem height, or diameter at breast height only as independent variables explained well the variation in inner bark yield. When paper mulberry was completely removed during the rice growing season, rice yields in these areas were similar to those following weedy bush fallow. When paper mulberry was allowed to grow, rice yields were negatively correlated to paper mulberry stem density. When paper mulberry lateral branches were pruned back, rice yields could be maintained if the paper mulberry stem density was <0.22 stems m−2, suggesting that if paper mulberry is managed properly, rice yields can be maintained at current levels. The paper mulberry-upland rice rotation system improves the productivity of a traditional slash-and-burn system through harvesting paper mulberry inner bark; however the long-term sustainability of such a system remains unclear and warrants further investigation.  相似文献   

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