油茶湘林系列6个无性系嫁接苗生长调查

对湘林系列5、14、15、18、40、166等6个油茶优良无性系的芽苗砧嫁接苗生长情况进行了调查。调查结果为：6个无性系平均成活率和抽梢率的变化范围分别为74．6％-96．2％和71．3％-93．6％，平均苗高和地径的变化范围分别为13．5-19．8cm和0．303-0．356cm，平均叶片数和冠幅值变化范围分别为8．7-12．7片／株和7．3-8．6cm，平均根长和根幅变化范围分别为6．0-6．8cm和4．7-6．5cm。6个无性系平均成活率和抽梢率分别为85．O％和88．5％，分别大于对照5．0％和2．1％；平均苗高和地径分别为15．8cm和0．33cm，分别大于对照1．4cm和0．022cm；平均叶片数为10片／株，大于对照0．8片／株；平均冠幅、根长和根幅分别为8．0cm、6．5cm和5．4cm，分别大于对照0．43cm、0．25cm和0．78cm。湘林166和湘林5的芽苗砧嫁接苗生长表现较好，其平均成活率、抽梢率及苗高、地径、叶片数量、冠幅与根长等均较大；湘林15和湘林40则生长表现较差，其平均成活率、苗高、叶片数量等均略低于混合优良无性系（对照）苗。     

川西南干热河谷地区引种巨尾桉人工林生态经济效果的初步研究

1999年 7月 ,从广西引进半年生巨尾桉组培苗 ,在攀枝花市仁和地区试种 34hm2 。测定结果 2 4年生巨尾桉林分的平均胸径为 6 1cm ,平均树高为 6 6m ,平均立木蓄积量为 32 33m3 ·hm-2 ;林分生物量及生产力分别为 2 5 85t·hm-2 和 10 77t·hm-2 ·a-1;林地枯枝落叶累积量及其最大吸水量分别为 7 11t·hm-2 和37 0t·hm-2 ,分别比草坡地高 2倍～ 5倍 ;林地土壤 (0～ 4 0cm)容量为 1 36g·cm-3 ～ 1.4 5g·cm-3 ,比草地略低 ;土壤总孔隙度及通气度分别为 5 1 2 9%～ 6 2 32 %和 19 5 5 %～ 2 6 38% ,分别比草地略高 ;土层最大、毛管及最小持水量分别为 34 93%～ 4 5 31%、31 5 4 %～ 39 82 %、2 1 94 %～ 2 6 32 % ,相应比草地略高 ;林内日平均气温及日较差分别为 2 2 2℃～ 2 3 1℃和 4 4℃～ 8 9℃ ,分别比草地低 0 2℃～ 2 4℃ ;林内空气相对湿度日均值为 80 %～ 88% ,比草地高 3%～ 16 %。初步显示出巨尾桉人工幼林的生态经济效益     

GA激活剂在抗旱造林中的初步研究

通过应用新型的抗旱保水造林材料——GA激活剂在干旱石质山地中进行造林试验研究，结果表明：应用GA激活剂进行的3个树种的造林效果，平均成活率比对照提高了5％～28％，其中，刺槐、火炬树、黄栌应用2kg GA激活剂的效果分别比对照提高了12．4％、37．1％、4．8％，使用1kg GA激活剂的刺槐和火炬树分别提高了5％和19．3％。适宜用量的GA激活剂具有较明显的保水作用，经过4个月后，在0～20cm层次中，GA激活剂处理的土壤平均含水量是对照的1．8倍，在20～40cm层次中是对照的近0．5倍。在GA激活剂的使用上应根据不同树种的特性选择用量与使用方式。     

接种线虫对复垦铜尾矿地碱解氮及氮素矿化的影响

在室内恒温（20℃）控制性培养1个月和2个月后,研究了土壤线虫活动对铜尾矿复垦地土壤碱解氮以及氮素矿化的影响。实验分别设置草、小飞蓬和茅草3种优势植被土下的3个处理：①不接种线虫的对照处理（－Nem ）;②培养盆内接种125条线虫处理（＋125Nem ）;③培养盆内接种250条线虫处理（＋250Nem）,每个处理设置3个重复。实验结果显示：无论是1个月还是2个月为周期的室内培养,在以铜尾矿复垦地土壤为供试土壤中接种线虫处理（＋125Nem ,＋250Nem）的土壤碱解氮含量较相应的对照处理（－Nem）有显著性提高（p＜0．01）。草优势植被土下接种线虫（＋125Nem ,＋250Nem）1个月周期内碱解氮含量分别是对照处理（－N em ）的4．05倍和5．72倍,2个月周期内分别是5．58倍和7．04倍;小飞蓬优势植被土下接种线虫（＋125Nem ,＋250Nem）1个月周期内碱解氮含量分别是对照处理（－Nem）的3．01倍和4．31倍,2个月周期内分别是4．07倍和5．67倍;茅草优势植被土下接种线虫（＋125Nem ,＋250Nem）1个月周期内碱解氮含量分别是对照处理（－N em ）的2．07倍和2．96倍,2个月周期内分别是2．90倍和3．93倍。通过相关数据计算这两个周期内土壤的氮素矿化速率发现,接种线虫后（＋125Nem ,＋250Nem ）,土壤的氮素矿化速率显著高于（p＜0．01）相对应的不接种线虫对照处理（－Nem）,并且在2个月培养期内接种250条线虫处理（＋250Nem）条件下达到最高值。     

准格尔旗黄土丘陵区人工林水文生态效益评价研究

就黄土丘陵区主要植被类型人工油松成熟林、人工油松中龄林、人工油松幼龄林、人工沙棘林、人工柠条林、天然草坡的枯落物容水特征和林地土壤水分物理性质进行了测定,并以坡耕地作对照。结果表明：人工油松成熟林的枯落物吸水量为22．6t／hm2,是中龄林和幼龄林的5～9倍,是灌木林的2．4～3倍,是天然草地的10倍多。0～40cm土层土壤最大持水能力油松成林、油松幼林、浦松中龄林、人工沙棘林、人工柠条林、天然草地、农耕地依次为2260．05、1935．6、1935．6、1820．1、1597．65、1666．05、1600．2t／hm2;油松成林、油松幼林、油松中龄林、人工沙棘林、天然草地0—40cm土层土壤最大持水能力分别比对照农耕地提高659．85、335．4、335．4、219．9、65．85t／hm2。在土壤总孔隙度、毛管孔隙度、毛管最大持水量、土壤最大持水能力等水土保持及水源涵养功能指标诸方面,人工油松林均优于灌木林和天然草地。     

竹林林下植物多样性与土壤水分入渗关系的研究

研究分别以浙江安吉县的4种林分类型(毛竹纯林(A)、毛竹+乔木(B)、毛竹+灌草(C)、乔木+灌草(D))以及湖南炎陵县3种林分类型(毛竹+乔木、毛竹+灌草、乔木+灌草)为对象,探讨了不同类型竹林林下植物多样性与其下不同深度土壤根系重量之间的关系,以及土壤渗透速率与不同土层根系重量和土壤含水量的相关性.结果表明:(1)上述4种植被类型0 ～40 cm根系生物量约为40～80cm的3倍,各类型林下植物多样性与其不同土层的根系重量相关性不显著;(2)浙江安吉4种植被类型中,0～40 cm与40～80 cm土层的渗透性指标以毛竹+乔木较好,初渗率、稳渗率和平均渗透率平均分别为:15.38、5.26和8.8 mm·min-1;毛竹纯林上述3项指标较低,平均分别为:5.83、3.03和4.45mm·min-1;湖南0～40 cm土层毛竹+乔木渗透性最好,上述三项指标分别为:16.72、12.23和9.13mm/min,40～ 80 cm各植被类型渗透性相差不大;(3)浙江毛竹+乔木、乔木+灌草土壤含水量均随土壤深度增加而降低,毛竹纯林与毛竹+灌草土壤含水量随土壤深度增加而先降低到18％后逐渐升高最终稳定在19％;(4)土壤入渗速率与不同深度土层根系重量显著相关,但根系重量不是决定土壤渗透性能的主要因素;(5)0 ～40cm土层的累计入渗量和土壤初始含水量呈典型的负相关,而40～80 cm土层的累计入渗量和土壤初始含水量没有明显的相关关系.     

京桃果实发育特征的观测

以吉林向海国家级自然保护区管理局院内绿化栽培的京桃为材料,对其果实发育特征进行观测,结果表明:在2018年通榆地区的生态环境条件下,京桃果实具有早期发育快于后期的特点。发育的1~3周时,每周体量以0. 70~1. 67倍的速度增加;4~8周时,每周体量仅以0. 1~0. 2 cm的速度增加。三种果形从满一周的纵径0. 4 cm、宽横径0. 3 cm分别增加到2. 3 cm与2. 2 cm、2. 4 cm与2. 5 cm、2. 6 cm与2. 2 cm,分别增加了4. 8倍与6. 3倍、5. 0倍与7. 3倍、5. 5倍与6. 3倍。发育过程中果实的果皮呈绿色,7月下旬开始逐渐变黄,8月上旬为"杏黄色",完全成熟并陆续脱落。     

岷江上游干旱河谷岷江柏木幼林地绿肥种植研究

在岷江上游干旱河谷岷江柏木幼林地经过连续4 a利用雨季种植绿肥压青,增加土壤肥力,提高水分利用率,促进幼树生长研究。结果表明:(1)种植红豆草的土壤0～40 cm含水量旱季增加3.68 g·kg-1,0～20 cm土壤容重降低0.07 g·cm-3;种植草木樨土壤0～40 cm含水量旱季增加4.18 g·kg-1,0～20 cm土壤容重降低0.05 g·cm-3;种植沙打旺土壤0～40 cm含水量增加2.46 g.kg-1,0～20 cm土壤容重降低0.18 g·cm-3。(2)种植绿肥压青,土壤有机质增加0.37 g·kg-1～0.55 g·kg-1,土壤CaCO3含量下降0.66 g·kg-1～1.36 g·kg-1,有效氮增加4.5 mg·kg-1～18.5 mg·kg-1,有效磷含量增加1.0～3.46 mg·kg-1,CEC比对照增加0.54～0.58mg.100g-1。(3)种植红豆草、草木樨、沙打旺绿肥压青对岷江柏木树高、地径生长有显著的促进作用,尤其种植红豆草的岷江柏木幼树生长最好,高、径生长为对照的1.7倍和1.6倍。     

永安市人工促进天然阔叶林更新效果分析

经过人工促进天然更新,永安市2．5年生阔叶林分平均胸径、树高、密度分别为1．8cm、3．2m、28767株·hm-2,乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为33、3．07、0．65和0．20,林分相对直径分布范围O．28—3．33cm,直径分布为反J型,表现为异龄林特征。55年生的伐前林分平均胸径、树高、密度分别为16．6em、11．3m、870N·hm2,乔木层物种丰富度R、多样性指数SW、均匀度E和生态优势度ED分别为21、3．83、0．87和O．08,林分相对直径分布范围0．36—2．89cm,直径分布为反J型,表现为异龄林特征。表明人工促进天然更新是天然阔叶用材林重要和有效的更新方式。     

樟子松人工林伐前人工更新技术

1试验地概况第1组试验地面积为3．3hm2，设在北坡，坡度11°的山腹上。上层樟子松人工林1962年营造，林龄32年。从1979年开始共进行过3次抚育问伐，现每公顷保留800株，林分平均胸径19．9cm、平均树高14．8m、蓄积量179．328m3／hm3、郁闭度0．7。第2组试验地面积为2．0hm2，设在北坡，坡度13°的山腹上。上层樟子松人工林1962年营造。从1979年开始进行过3次抚育间伐，现每公顷保留875株，林分平均胸径为17．4cm、平均树高14．5m、蓄积量144．322m3／hm2、郁闲度0．8。对照区设在与第1组试验地同一山腹相同的樟子松人工林内，面积3．0hm2。…     

Characteristics of carbon and nitrogen of soil microbial biomass and their relationships with soil nutrients in Cunninghamia lanceolata plantations

The soil microbial biomass and nutrient status under the native broadleaved forest and Cunninghamia lanceolata plantations at the Huitong National Research Station of Forest Ecosystem (in Hunan Province, midland of China) were examined in this study. The results showed that after the native broadleaved forest was replaced by mono-cultured C. lanceolata or C. lanceolata, soil microbial biomass and nutrient pool decreased significantly. In the 0–10 cm soil layer, the concentrations of soil microbial carbon and nitrogen in the broadleaved forest were 800.5 and 84.5 mg/kg, respectively. These were 1.90 and 1.03 times as much as those in the first rotation of the C. lanceolata plantation, and 2.16 and 1.27 times as much as those in the second rotation of the plantation, respectively. While in the 10–20 cm soil layer, the microbial carbon and nitrogen in the broadleaved forest were 475.4 and 63.3 mg/kg, respectively. These were 1.86 and 1.60 times as much as those in the first rotation, and 2.11 and 1.76 times as much as those in the second rotation, respectively. Soil nutrient pools, such as total nitrogen, total potassium, NH₄ ⁺-N, and available potassium, also declined after the C. lanceolata plantation replaced the native broadleaved forest, or Chinese fir was planted continuously. Less litter and slower decay rate in pure Chinese fir plantation were the crucial factors leading to the decrease of soil microbial biomass and nutrient pool in this area. Human disturbance, especially slash-burning and site preparation, was another factor leading to the decrease. There were significant positive correlations between soil microbial carbon and nitrogen and soil nutrients. To improve soil quality and maintain sustainable productivity, some measures, including planting mixed conifer with hardwood, preserving residues after harvest, and adopting scientific site preparation, should be taken. Translated from Chinese Journal of Applied Ecology, 2006, 17(12): 2,292–2,296 [译自: 应用生态学报]     

用木蜡修饰土壤颗粒抑制沙土水分蒸发的研究(英文)

本文目的拟解决荒漠化地区土壤自涵养水分的问题。用分子化天然木蜡通过筛选的特种表面活性剂修饰土壤颗粒表面,将该颗粒构造于模拟沙漠气候的人工气候箱内的试验沙土表面,形成一层透气抑水的土膜,利用水分测定仪、差示热分析仪、X射线衍射、红外光谱等方法研究了该土膜的结构、保水机理和对草生长的影响。结果表明,采用山梨醇酐单硬脂酸酯(Span80)对木蜡和粘土颗粒均有有效的分散和分离作用,并使木腊均匀结合于粘土表面,使粘土颗粒间隙变小,亲水孔变为憎水孔,增加了蒸发水分穿透膜层的阻力,实现了土膜的保水功能,在模拟的沙漠气候人工气候箱内实现了草的正常生长。     

Agroforestry on alkali soil: effect of planting methods and amendments on initial growth,biomass accumulation and chemical composition of mesquite (Prosopis juliflora (SW) DC) with inter-space planted with and without Karnal grass (Diplachne fusca Linn. P. Beauv.)

Growth responses of mesquite (Prosopis juliflora (SW) DC.) during establishment stage to planting methods and amendments were studied in a highly alkali soil (Aquic Natrustalf, ESP 94), at the experimental farm of the Central Soil Salinity Research Institute, Karnal in July, 1984. Six combinations of planting methods and amendments with and without Karnal grass (Diplachne fusca Linn. P Beauv) in the inter-row space were compared in a four times replicated field experiment in randomised block design. The mean plant height (MPH), diameter at stump height (DSH), diameter at breast height (DBH), lopped biomass 16 months past planting and total biomass attained in 2 years period were significantly less when inter-row space was planted with Karnal grass. The MPH (cm), DSH and DBH (mm) attained in 2 years period were 319, 43.4 and 15.1 in with grass as compared to 405, 53.4 and 20.3 in without grass treatments. Similarly, the total biomass attained in 2 years was about 3 times more where inter-row space was not planted with grass. Growth was better when mesquite was planted by auger hole and pit methods than in trench plantation, when the original soil was treated with gypsum at 3 kg plant^–1 and then refilled. However, using trenches of dimensions 30 × 30 cm and filled with a mixture of original soil, 3 kg gypsum and 8 kg farm yard manure plant^–1 appeared to be promising method for establishing mesquite plantations on highly deteriorated alkali soils. The effect of amendments on growth decreased in the order gypsum + FYM, gypsum + rice husk, gypsum, control. In two years period, 37 percent mesquite died in the trenches in which the original soil was left unchanged. Effect of treatments on nutrient concentrations and total accumulations in different segments of mesquite is discussed. Karnal grass gave 25.3 t ha^–1 green forage yield in 8 cuts without amendment in a growth period of 26 months proving its great potential as a folder crop for the adverse sites. The inorganic chemical composition of the shoots, including trace elements Fe, Mn, Zn and Cu, is such as to make this species a highly promising plant for the exploitation of alkali soils. Growing Karnal grass with mesquite for a period of about 2 years reduced soil pH and EC significantly and improved organic carbon and available N contents. The grass improved water infiltration rates and moisture storage in the lower layers of the profile.     

红壤退化地杨梅林土壤对养分补偿的响应

2016年在福建省长汀县河田镇车寮村杨梅园以东魁杨梅(Myrica rubra cv.DongKui)林为试验材料,在了解当地东魁杨梅的栽培情况及对林下土壤养分分析的基础上,开展复合肥、菌肥、磷肥、菌肥+磷肥4种土壤养分补偿试验,分析0～20、20 ～ 40 cm土层对不同土壤养分补偿方式的响应.结果 表明:在pH值响...     

Effects of coastal afforestation on some soil properties in Lakshmipur coast of Bangladesh

Coastal zones comprising important intertidal tropical and subtropical ecosystems are characterized by high productivity, diversity and unique zonation of various plant and animal communities. The comparison of some selected physicochemical soil properties viz. texture, particle density, moisture content, pH, organic carbon and total nitrogen between planted site （Telir char） and barren site （Boyar char） has been investigated at surface （0-10 cm） and subsurface （10-45 cm） soil across three different land strips viz. inland, middle part and sea side in Lakshmipur coast of Bangladesh. Sand particles in the soil were lower in planted site than barren site. The reverse trend was found in case of both silt and clay percentage. Coastal afforestation had a significant effect on soil binding process since a common trend of increment in soil particle density was noticed. Maximum increment （20.43% to 23.30%） in soil moisture content was recorded in surface soil across the seaside while at subsurface soil both across the middle part （19.53% to 22.30%） and sea side （20.19% to 22.96%）. Moreover, the highest reduction in soil pH was recorded at surface soil （7.27 to 6.60） across the sea side and subsurface soil （7.16 to 6.67） in inland due to the influence of coastal plantation. Across all the land strips and the soil depths studied, soil organic carbon was higher in planted site than in barren site with only exception at subsurface soil in the middle part （0.50% in both sites）. Total soil nitrogen in the study area was increased at both depths due to forestation with the highest increment in the inland at both surface and subsurface soil.     

矿渣区复土种植促进欧李生长和营养吸收效果试验研究

为改善矿区遗留矿渣土质,推动资源环境协调发展。该研究以陕西韩城两片矿渣土为研究对象,分析了矿渣土复土和不复土对欧李的生长、干物质累积和养分吸收的影响。结果表明:与矿渣土种植相比,复土改良种植的欧李株高和分枝数显著(P<0.05)提高了52%和140%;茎、叶、果和总干物质累积量显著(P<0.05)提高了4.78、3.96、3.89和4.1倍;植株全氮、全磷、全钾累积量显著(P<0.05)提高了6.1,5.7和5.8倍,且促进了养分向果实的转运。复土改良促进了作物生长和凋落物的堆积,丰富了土壤养分,不仅提高了土壤肥力且显著促进了作物的生长,形成了改善土壤质量的良性循环。建议在矿渣土表层覆盖30cm土壤,种植作物。     

Grazing impacts on spatial distribution of soil and herbaceous characteristics in an Australian tropical woodland

This study examined effects of different levels of applied grazing pressures on herbaceous vegetation (standing crop, basal area, size and spacing of grass tussocks) and soil properties (total soil C, total N, total P, and soil-borne plant material [roots and surface litter] in the A horizon) around grass tussocks of a dry eucalypt woodland (dominant woody components; Eucalyptus xanthoclada and Corymbia erythrophloia of northern Australia. Grass tussocks influenced total soil C and N at small (<20 cm) spatial scales, and applied grazing pressures significantly (p<0.05) affected all soil properties except total P. Concentrations of N and C were highest at locations close to plants, and levels in proximity to plants declined under sustained heavy grazing. Paddocks receiving heavier grazing pressures also produced less standing crop and tussocks were smaller and more widely dispersed. Further, areas with high amounts of soil C, N and soil-borne plant materials were smaller and more widely dispersed under heavy grazing. Alternatively, conservative grazing pressure in combination with wet season grazing deferments allowed conservation of landscape condition. Eucalypt woodlands in northern Australia have low resistance to disturbance, and limited resilience to recover following disturbance. As such, the effects of disturbance on these areas should be monitored by combinations of plant (basal area, plant spacing) and soil (soil-borne plant material, total N) characteristics capable of detecting degradation at the earliest stages possible.     

Combining napier grass with leguminous shrubs in contour hedgerows controls soil erosion without competing with crops

We established hedges/barriers of calliandra (Calliandra calothyrsus Meissner), leucaena (Leucaena trichandra (Zucc.) Urban)) and napier grass (Pennisetum purpureum Schumach) and combination hedges of either calliandra or leucaena with napier grass on slopes exceeding 5% to study the effect of vegetative barriers on productivity of arable steep-lands in central Kenya. Hedges/barriers were pruned regularly and biomass incorporated into the plots. Hedge plots were monitored for soil fertility, soil losses and maize crop yield changes. Inorganic-N concentration in the tree hedge plots was higher than in the control and napier barrier plots after 20 months. Napier grass barriers were the most effective in reducing erosion losses across the two seasons. The effectiveness of napier grass to significantly reduce soil erosion was detectable in one year old napier barriers. Soil loss from all the other one year old vegetative treatments was similar to soil loss from the control. Seventeen month old combination hedge plots recorded lower soil losses than tree hedges of the same age (P = 0.012). Maize crop yields throughout the trial period were high and similar for leguminous and combination hedge plots, but lower in the napier grass and control plots. Overall, we observed that the combination hedges seemed to provide a win-win scenario of reduction in soil erosion combined with improvement of maize crop yields and soil fertility enhancement. We conclude that vegetative hedges have a potential for improving soil productivity in arable steep-lands of the central highlands of Kenya, and that in adoption of vegetative hedges for this purpose there are trade-offs between soil conservation, soil fertility and maize crop yields to be considered. Throughout the text, tree hedges and leguminous hedges are used interchangeably to imply calliandra and leucaena hedges while use of barrier/s to refer to a treatment is restricted to monospecific grass strips     

Effectiveness of sloping agricultural land technology on soil fertility status of mid-hills in Nepal

Hedgerows with intercropping systems were established at the ICIMOD test and demonstration site at Godawari to assess the effective-ness of Sloping Agricultural Land Technology (SALT) in reducing run-o...     

Microbial community diversity in agroforestry and grass vegetative filter strips

Vegetative filter strips (VFS) have long been promoted as a soil conservation practice that yields many additional environmental benefits. Most previous studies have focused primarily on the role of vegetation and/or soil physical properties in these ecosystem services. Few studies have investigated the soil microbial community of VFS. Therefore, we examined potential differences in soil microbial community characteristics of claypan soil planted to VFS with differing vegetation and a traditional row-crop system in a maize–soybean rotation. Samples were tested for soil microbial function and community structure using dehydrogenase and fluorescein diacetate (FDA) hydrolysis enzyme assays and phospholipid fatty acid (PLFA) analysis, respectively. The grass VFS soil exhibited the greatest dehydrogenase activity levels and FDA activity was greater in the grass and agroforestry (i.e., tree–grass) VFS soils relative to the cropland soil. The PLFA analysis revealed community structural differences underlying these functional differences. The agroforestry VFS soil was characterized by a greater proportion of total bacteria, gram-negative bacteria, anaerobic bacteria and mycorrhizal fungi than the cropland soil. The grass VFS soil shared some characteristics with the cropland soils; but the grass VFS supported greater mycorrhizal fungi and protozoa populations. This work highlights differences in soil microbial function and community structure in VFS relative to cropland soil 12 years post VFS establishment. It also enhances our fundamental knowledge regarding soil microorganisms in VFS, which may aid in explaining some ecosystem services provided by VFS (e.g., decomposition of organic agrichemicals).