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在3种施肥处理(1 m沟施、2 m沟施和3 m沟施)和沟上和沟外2种取样位置下,研究了毛竹林细根(0~5 mm)生长特征。结果表明,毛竹林细根生物量为5.16~10.54 t/hm2,平均为6.87 t/hm2。从施肥处理看,沟上细根生物量、根长、根尖数、根表面积和根体积在施肥量0.36 kg/m的3 m沟施处理下,均显著高于施肥量为0.14 kg/m的1 m沟施和0.26 kg/m的2 m沟施处理(p < 0.001);从取样位置看,在3 m沟施处理下,沟上细根根长、根尖数和根表面积均显著高于沟外取样点(p < 0.05)。可见,在施肥沟上(或更大的施肥量下)的细根生长量较大,体现了毛竹林细根生长的"趋富特化"现象。 相似文献
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1 插壤选择及消毒处理 以砂质壤土最好,土壤含盐量不超过0.2%。插壤运至温湿大棚内,每667m2施用肥料及药剂如下:棉饼125.0kg,尿素25.0kg,磷肥50.0kg,呋喃丹2.5kg,甲拌磷1.0kg,代森锰锌0.5kg,甲基托布津0.5kg。2 作床及脱钵 插壤经整平后,将肥料、杀虫及灭菌类药剂均匀地撒于插壤表层,经过筛,再次平整土壤。苗床的宽度以1.0～1.2m为宜,长度不限,以方便苗木管抚为佳,苗床之间须留30～40cm宽的人行步道。用水足量地浇透插壤,隔日即可进行脱钵。用起钵器将插壤制成高10cm,直径7cm的圆柱形营养钵。3 种根的收集及根插穗的剪切3.1 种根… 相似文献
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尾巨桉和厚荚相思人工林细根主要营养元素贮存量及其季节动态研究 总被引：1，自引：0，他引：1
通过对广西东门林场某分场5年生尾巨桉和厚荚相思人工林细根主要营养元素(N、P、K、Ca、Mg)贮存量及其季节动态进行的研究,结果表明:尾巨桉、厚荚相思人工林细根5种营养元素贮存量随季节不同而存在差异。不同季节尾巨桉人工林细根营养元素贮存量大小次序为夏季(6.514kg·hm-2)秋季(6.452kg·hm-2)春季(5.089kg·hm-2)冬季(4.524kg·hm-2);厚荚相思人工林细根相应为夏季(13.920kg·hm-2)秋季(11.523kg·hm-2)春季(3.620kg·hm-2)冬季(2.902kg·hm-2)。 相似文献
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对不同经营方式的绿竹林根系结构和生物量分布开展了研究,结果表明:在粗放经营的绿竹林内,竹根干质量总量为317.61 kg·hm-2,竹根长度总量为45 304.91 m·hm-2,竹根表面积总量为98.65 m2·hm-2,竹根体积总量为0.018 1 m3·hm-2;在集约经营的绿竹林内,竹根干质量总量为1 333.12 kg·hm-2,竹根长度总量为143 338.46 m·hm-2,竹根表面积总量为3 089.15 m2·hm-2,竹根体积总量为0.583 1 m3·hm-2.无论是粗放经营的绿竹林,还是集约经营的绿竹林,0～40 cm土层都是竹根干质量、长度、表面积、体积4项指标集中分布的区域.在粗放经营的绿竹林中,0～20 cm土层竹根干质量、长度、表面积、体积4项指标所占比例最高;而在集约经营的样地中,20～40 cm土层4项指标所占比例最大.在粗放经营的绿竹林中,总生物量干质量为14 537.34 kg·hm-2,其中地上部分为12 575.34 kg·hm-2,地下部分为1 962.00 kg·hm-2;而在集约经营的绿竹林中,总生物量干质量为39 267.27 kg·hm-2,其中地上部分为31 518.27 kg·hm-2,地下部分为7 749.00 kg·hm-2.比较集约经营、粗放经营的绿竹林各组分生物量,发现集约经营绿竹林远大于粗放经营绿竹林,其中差异最大的是叶,集约经营绿竹林是粗放经营绿竹林的5.68倍,其次是根,为4.23倍,差异最小的是秆,为2.03倍,生物量差异大小的顺序为:叶＞根＞枝＞蔸＞秆.在各组分生物量所占的比例中,集约经营、粗放经营绿竹林表现出相同的特征,即各组分生物量所占比例的大小为:秆＞枝＞蔸＞叶＞根. 相似文献
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<正>山东省滨州市惠民县路家村,利用沙荒地栽植苹果24 hm2,主栽品种短枝红富士和新红星,株行距3m× 4 m。通过综合管理,实现了 3年见果,6年每 667m2产量达 2 258kg。主要栽培技术如下:1 高标准建园 栽植前1年秋季细致整地,先将高低不平的沙丘推平,然后挖1m见方大穴,用熟化土换掉上层沙土。春季定植造林,栽植时每株施入60kg土杂肥、1kg磷肥、0.5 kg磷酸二铵、150 g硫酸亚铁作底肥。苗木选用2年生苗高 1.5 m、根径 1.2 cm以上的壮苗,栽后灌足水,然后每株用1m2见方的地膜覆盖树盘,以保水、保墒,提高成活率。 相似文献
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对中国林科院亚热带林业研究所所部大垅粗放经营毛竹林地下鞭系和根系结构进行了研究,采用WinRHIZO根系分析系统,分析了竹根、鞭根各项数量指标.结果表明:粗放经营毛竹林鞭系总干质量、体积、长度和表面积分别为6 179.44 kg·hm-2、24.57 m3·hm-2、84 872.99 m·hm-2和5 066.10 m2·hm-2,竹鞭集中分布在030 cm土层中.粗放经营毛竹林竹鞭以34年生最多,各项指标均占40%左右,12年生竹鞭比例很小,占10%左右,且主要分布在030 cm土层,占该年龄竹鞭总质量的92.65%.粗放经营毛竹林竹根、鞭根干质量分别为3 564.92、5 506.28 kg·hm-2,长度分别为2.24×107、6.40×107 m·hm-2,鞭根数量大于竹根量,鞭根干质量、长度、体积和表面积分别是竹根的1.55、2.86、1.80和2.52倍.在竹林地下系统中,鞭系干质量占40.52%,体积占67.56%,根系总长度约是鞭系总长度的1 000倍,根系的总表面积也是鞭系的20多倍. 相似文献
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1 全枣林(园)培育根蘖壮苗选择品质好、质量高、生长健壮的母枣树林在冬季封冻前或早春解冻后,结合枣林全面浅耕,每公顷散施人粪尿2250kg 和碳氨75kg 左右,同时,在距树干1.5～2m处挖15～20cm 深的沟,损伤表土中较细的根系,保护好2cm 以上粗大的水平根,刺激浅层的水平根在伤口处和伤口附近形成不定芽,抽生根蘖苗。每公顷可产苗900 相似文献
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岷江干旱河谷-山地森林交错区典型人工林细根生物量及其碳储量特征 总被引：5，自引：0，他引：5
细根在森林生态系统的物质循环和能量流动中具有十分重要的和不可替代的作用.为了解岷江干旱河谷-山地森林交错带人工林生态系统功能,研究了该区青冈人工林(QF)、人工混交林(BF)、粗枝云杉人工林(SF)、沙棘灌木林(HP)和刺槐人工林(RP)五种典型森林群落细根的生物量及其碳储量特征.不同森林群落细根生物量和碳储量均随着土壤深度增加而降低,并与土壤发育程度和树种有关;细根主要分布土壤表层0～20 cm范围内,平均占细根总量的87%,大于20 cm细根也有分布,仅占细根总量的13%;QF、BF、SF、HP和RP细根的生物量分别为3 820 kg·hm-2、2 036 kg·hm-2、1 855 kg·hm-2、1 816 kg·hm-2和1 144 kg·hm-2,碳储量分别为1.91MgC·hm-2、1.02 MgC·hm-2、0.93 MgC·hm-2、0.91 Mgc·hm-2和0.57 MgC·hm-2. 相似文献
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不同鱼腥草生物特性及高效高产栽培技术研究 总被引：2，自引：0，他引：2
对鱼腥草的生物学特性进行了调查观察,特别对鱼腥草的人工栽培技术等方面进行了探索研究。收集鱼腥草种质资源23个,进行种植保存;并建立30多亩生产示范基地。结果：不同种源鱼腥草主要经济性状存在显著差异,其中地上茎叶产量以11号处理最高干品产量达0.93kg/m^2,比最低的10号处理0.38kg/m^2高144.74%。地下根鲜产量以处理4最高达5.5kg/m^2,比最低的17号处理1.7kg/m^2高223.53%;通过对23个种源地上干品产量、地下根鲜品产量统计比较结果,可选用11号、17号、16号等作为售茎叶为主的药用栽培品种,3号、4号、13号等作为售鲜根为主的菜用栽培品种。在栽培地上套种吊瓜可增产增效。 相似文献
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El Amin Yousif Raddad 《New Forests》2007,34(3):207-222
The genetic variation in seed weight, seed number per kg and seedling traits was compared among eight Acacia senegal provenances originating from the clay plain (east) and sand plains (west) of the gum belt in Sudan. The main objective of
this study was to identify germplasm sources of A. senegal that have a good seed germination capacity and seedling traits suitable for reforestation in the clay-soil part of the dryland
gum belt in the Blue Nile region in Sudan. A specific objective was to tentatively explore the adaptive strategy of A. senegal populations. Seventeen-week-old seedlings were planted in the field at spacing of 3 m × 3 m, giving 100 trees per plot and
replication; within a randomized complete block design with four replications. The experimental site was in the clay plain
region. Seed variables showed significant differences. Clay plain provenances showed considerable variation in seed weight
and seed number. They had the smallest seed weight but the highest seed number, while the sand (western) provenances had the
largest seed weight but lowest seed number. Seedling branch number, root length, root to shoot ratio and shoot dry weight
differed significantly among the provenances 12 weeks after germination. Clay provenances had the highest branch number and
shoot dry weight but the shortest roots and lowest root to shoot ratio. This was interpreted as showing better adaptation
to the site in these local provenances in comparison to those originating from the western sandy soil regions. High positive
correlations were observed between seedling variables, such as root nodule and branch numbers; this could be used for early
selection. The variation was greater between provenance groups than within them, suggesting that especially selection among
groups would yield genetic gain. 相似文献
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Post-storage water relations, stomatal conductance, and root growth potential were examined in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedlings from high- and low-elevation seed sources that had been lifted either in October or November and freezer stored, or in March, and then grown hydroponically in a greenhouse for 31 days. Seedlings lifted in October had poor root initiation (< 17 new roots per seedling), low predawn leaf water potentials (< -1.5 MPa), and low stomatal conductance (7.10 mmol m(-2) s(-1)) compared with seedlings lifted in November or March. There was little difference in post-storage water relations and stomatal conductance between seedlings lifted in November and those lifted in March. Throughout the 31-day test, seedlings from the high-elevation seed source produced 3-9 times more new roots, had higher predawn leaf water potentials (-0.6 to -0.7 MPa versus -1.1 to -1.6 MPa), and 1.3-5 times greater stomatal conductance than seedlings from the low-elevation seed source. For all seedlings on Day 31, the number of new roots was significantly related to predawn leaf water potential (r(2) = 0.65) and stomatal conductance (r(2) = 0.82). Similarly, the dry weight of new roots per seedling on Day 31 accounted for a significant amount of the variation in predawn leaf water potential (r(2) = 0.81) and stomatal conductance (r(2) = 0.49). 相似文献
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Coarse root growth of Veronese poplar trees varies with position on an erodible slope in New Zealand
Poplars are commonly planted on moist, unstable pastoral hill country to prevent or reduce soil erosion, thereby maintaining
hillslope integrity and pasture production. Mechanical reinforcement by poplar root systems aids slope stabilisation, particularly
when the roots are anchored into the fragipan or underlying rock. Total root length, mass and distribution of coarse roots
(≥2 mm diameter) were determined for three Populus deltoides × nigra ‘Veronese’ trees in their 12th growing season after being planted as 3 m poles at upper slope (TU), mid-slope (TM) and lower
slope (TL) positions on an erodible hillslope near Palmerston North in the southern North Island. Most of the roots were distributed
in the top 40 cm of soil. Depth of penetration of vertical roots was dependent on slope position and limited by the available
depth of the soil above a fragipan (0.35 m at the upper slope to 1.4 m at the lower slope). Roots penetrated the fragipan
at the upper slope position where the soil depth was shallowest, and at the mid-slope, but not the lower slope position. Total
coarse root length was 287.9 m for TU, 1,131.3 m for TM and 1,611.3 m for TL, and total coarse root dry mass (excluding root
crown) was 8.15 kg for TU, 38.77 kg for TM and 81.35 kg for TL. 相似文献
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通过在砚山县铳卡农场对圣诞树、滇合欢、新银合欢、刺槐4个树种不同造林密度、施肥措施、苗根处理方式及苗期喷云大-120等5个因素的对比试验,幼树期的结果表明树种对林木生长量及生物量的影响最大,施肥措施和苗根处理方式对林木的生长发育也具有一定的作用,而苗期喷云大-120对定植后林木的生长发育作用不明显,密度效应除圣诞树外其他3个树种还不显著。参试的4个树种中,圣诞树3年生时已经郁闭,其最佳技术组合A1B1C1D1E1的树高、地径、冠幅和单株生物量分别为5.05m、4.72cm、1.79m和7.05kg,每公顷可提供薪材22678kg、绿肥和饲料24345.5kg,产值3485.08元;滇合欢的最佳技术组合A2B1C2D2E1的树高、地径、冠幅和单株生物量分别为1.84m、4.33cm、1.23m和1.26kg,每公顷可产薪材6936.8kg、绿肥和饲料1467.4kg,产值767.05元;新银合欢则不太适应试区的气候,每年都受霜冻的危害。预计在滇东南岩溶山区选择多用途的圣诞树和滇合欢,采用最佳的技术措施组合造林,能取得良好的生态效益和经济效益。 相似文献
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Size, dry weight and mineral nutrient content of fruit, leaves, shoots, canes, leader, stem and roots of kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa) vines, aged from one to five years, were measured. The distribution of fruit yield among single canes was examined in three of the vines. Total dry weight increased from a mean of 1.29 kg vine(-1) for one-year-old vines to 29.2 kg vine(-1) for five-year-old vines. The proportion of total dry weight in roots declined from the first to the third year (55 to 40%) and then remained approximately constant, whereas the proportion of dry weight in fruits increased from the first to the third year before attaining a more or less constant value. The proportion of total canopy dry weight contained in the current season's growth (fruit, leaves and shoots) averaged 75% for all ages. Roots of five-year-old vines had only penetrated a small proportion of the total soil volume available. Total fruit yield increased linearly with number of floral shoots for whole vines and single canes within vines, but with cane size (length or dry weight) for whole vines only. The productivity of single canes declined from 2.5 kg m(-1) for canes shorter than 0.25 m to about 1.1 kg m(-1) for canes longer than 1.0 m, in accordance with a declining bud density with increasing cane length. For vines of all ages, mineral nutrient concentrations in various tissues were similar, except that Ca in leaves and S in leaves and shoots increased with vine age. Major sites of accumulation of N, Ca, Mg, S, Fe, Mn and B were the leaves, whereas P and K accumulated predominantly in the fruits, Zn in the leader, and Na and Cu in the roots. Estimated annual mineral nutrient uptake increased with vine size and fruit yield, and for five-year-old vines the values per hectare were 141 kg N, 19 kg P, 169 kg K, 161 kg Ca, 28 kg Mg, 32 kg S, and less than 2 kg for Na and all micronutrients. The nutrient content of the harvested fruit provided an inaccurate estimate of annual nutrient uptake of the developing vines. 相似文献