有机肥替代不同比例化肥对麻竹笋产量的影响

在福建省南靖县开展了麻竹笋用林有机肥替代化肥的田间试验,采取氮总量控制,设置有机氮替代不同比例无机氮的试验处理,分析了各处理之间出笋数量和竹笋产量的差异性。结果表明,在总氮施入量一定的情况下,不同比例的有机氮施入量对增加出笋数量和竹笋产量的影响排序表现为67%>0%>100%>50%>CK>33%;当有机氮施入量占67%时出笋的数量和产量分别比单施化肥增加6.1%和10.3%,对促进麻竹笋生长和产量提升最明显。     

马莲小枣性状观察及优质丰产栽培技术

马莲小枣是河北省红枣名优特品种之一 ,主要分布在河北省中南部的枣强县一带。为了探索马莲小枣优质丰产栽培管理的经验 ,我们在枣强县孟庄建立了马莲小枣示范园。1　示范园基本情况示范园地处河北省中南部平原区的枣强县 ,占地面积 1 2 .67hm2 ,0～ 50cm土层为粘质土 ,50～ 1 0 0cm是胶泥土 ,1m以下是沙质土。含盐量0 .1 5 %～ 0 .2 6 % ,土壤 pH值 7.5左右。大陆性干燥气候 ,年平均气温 1 2 .9℃ ,极端最高气温为42℃ ,极端最低气温为零下 2 1 .5℃ ,年平均相对湿度 63 % ,年降雨量 50 0mm ,多集中在 7月份左右。多数年份春季干旱 ,年蒸…     

松褐天牛在病死木伐桩中种群动态的研究

该文对不同月份 1 2 0株松材线虫病死木的伐桩 (根 )调查表明 :有松褐天牛Monochamusaltenatus Hope产卵痕的伐桩占 47.5 % ;伐桩上松褐天牛幼虫蛀入孔数占产卵痕数的 85 .71 % ;其中有 1 0 .42 %的蛀入孔转移至伐桩的地下部分 ;伐桩上松褐天牛成虫羽化率为 67. 71 % ,其中伐桩地上部分的成虫羽化率为 66.2 8% ,伐桩地下部分的成虫羽化率为 80 %。为此 ,连根挖除病死木伐桩 (根 )统一进行烧毁或用溴甲烷薰蒸处理是松材线虫病除治的必要措施。     

油茶净光合速率与主要经济性状的相关性研究

以油茶品种XL67、XL1、CK为试材,研究了油茶净光合速率与主要经济性状的关系。结果表明:3个油茶品种种子不饱和脂肪酸含量高低依次为:XL67(90.57%)、XL1(89.54%)、CK(88.63%);油酸含量高低依次为:XL67(87.48%)、XL1(84.11%)、CK(82.44%);净光合速率与油酸、亚油酸含量均存在极显著相关关系,产量与油酸含量存在显著正相关。     

巨尾桉优良无性系的选择试验

5年生巨尾桉无性系不同品系调查分析表明,生长最好的品系为N品系,平均树高达13 60m,平均胸径13 67cm,平均单株立木材积0 0903m3;其次为L品系,平均树高12 62m,平均胸径13 59cm,平均单株立木材积0 0839m3。抗霜性最好的为L、K、32-10品系,受害率为3 3%。不同品系间材积、树高、胸径存在显著或极显著差异。     

全红杨组织培养与快速繁殖技术研究

为建立全红杨组织培养与快繁体系,以全红杨叶柄为外植体,进行不同激素配比对愈伤组织诱导、不定芽分化、生根培养等影响研究。结果表明:适宜愈伤组织诱导培养基为MS+6-BA0. 2 mg·L~(-1)+NAA 0. 05 mg·L~(-1)+蔗糖25. 0 g·L~(-1)+琼脂6. 0 g·L~(-1),诱导率96. 67%;适宜不定芽分化培养基为MS+6-BA 0. 5 mg·L~(-1)+NAA 0. 2 mg·L~(-1)+蔗糖30. 0 g·L~(-1)+琼脂6. 0 g·L~(-1),分化率100%;适宜生根培养基为1/2MS+IBA 0. 3 mg·L~(-1)+蔗糖20. 0 g·L~(-1)+琼脂6. 0 g·L~(-1),生根率100%。本研究也为选育杨树良种、种质资源保存、扩大栽培与推广等提供研究基础。     

基于Costanza模型的苏州湿地生态服务价值评估

文章采用Costanza生态系统评价模型评估了苏州湿地生态系统服务价值。研究结果表明,2015年苏州湿地生态系统服务总价值为1 003. 53亿元,其中调节服务、供给服务、支持服务和文化服务价值分别为883. 27亿元,67. 81亿元,34. 90亿元和17. 55亿元;单位面积生态系统服务价值中河流湖泊湿地最大,为38. 34万元/hm2,稻田及人工养殖塘最小,为1. 19万元/hm^2;在湿地生态系统服务价值中,河流湖泊湿地贡献率最高,达95. 46%,其次是沼泽湿地2. 78%,稻田与人工养殖塘分别为0. 92%和0. 84%。     

湘南千年桐优树的选择与评价

为给湘南千年桐采穗圃的建立和无性系的繁育提供优良的种质资源,以湖南省宜章县4年生千年桐林木为研究对象,从中以目测法选出了67株备选优树,根据千年桐的生物学特性,确定单株结果量、单株产果量、单株产油量、鲜果出籽率、干籽出仁率和干仁出油率等6个性状指标作为选优评价指标,根据67株备选优树6个性状指标的测定均值、标准差和极差建立了千年桐优树的综合评价体系,按此评价体系从67株备选优树中初选出了29株优树。在这29株优树中,Ⅰ级优树4株,其6项性状指标的测定均值分别为781.25个、18.13 kg、3.01 kg、42.13%、69.58%、57.60%,分别为67株备选优树的215.22%、193.49%、259.48%、105.09%、99.00%、110.73%;Ⅱ级优树10株,其6项性状指标的测定均值分别为593.10个、13.20 kg、1.77 kg、42.95%、74.24%、52.02%,分别为67株备选优树的163.39%、140.88%、152.59%、107.13%、105.63%、100.00%;Ⅲ级优树15株,其6项性状指标的测定均值分别为428.90个、11.00 kg、1.37 kg、37.84%、75.15%、54.86%,分别为67株备选优树的118.15%、117.40%、118.10%、94.39%、106.93%、105.46%。研究结果表明,文中建立的综合评价法可为湘南地区千年桐优树的选择提供一种科学的评价方法。     

塔河荒漠植被受损知多少

长期以来 ,我区的平原天然林的重要地位一直没有给予足够重视。就两大盆地来说 ,破坏荒漠植被的行为时有发生 ,塔里木盆地的胡杨林破坏严重 ,森林面积大幅下降。 2 0世纪 50年代末有胡杨林 52万 hm2 ,蓄积量 540万 m3。 1979年林业航视时胡杨林面积减少了 4 6% ,无水自然衰退占林木的 13%。若羌县阿尔干地区 0 .67多万 hm2胡杨林 2 0多年没有浇上水。森林生态恶化 ,向着荒漠化生态系统转化 ,将给农牧业生产、交通安全、石油开发带来更大的生态灾害。让我们的镜头聚焦到塔河流域荒漠林生存状况 :1　塔河两岸开荒地 60 %以上为荒漠灌木林塔河…     

陈山红心杉材性变异及其基因资源的研究成果通过专家鉴定

由江西省林科院和安福县陈山林场承担的省科技厅“陈山红心杉材性变异及其基因资源利用的研究”课题 ,是“九五”重点攻关项目。该课题在 1996～ 2 0 0 0年 5年间 ,从全国 7省 10个试点的 6个优良种源 ,采回样芯近 150 0个 ,进行木材纤维长度、基本密度、晚材率及红心杉比率测定比较 ,重点研究了陈山红心杉材的遗传变化规律。不同种源间红心材比率差异极显著 ,以安福陈山的红心材比率最大 ,18年生时胸径处达 50 .5% ,比其他 5个种源大 2 8.2 %～ 4 0 .0 %。广义遗传率在 0 .67～ 0 .87,说明有较高的遗传力和较好的选择效果。杉木林分红心材…     

不同灌溉量对油橄榄产量和果实品质的影响

采用盆栽称质量的方法,对盆栽油橄榄灌溉20%、40%、60%、80%、100%、120%、140%蒸腾蒸发量（ET0）,进行产量与果实品质研究。结果表明,灌溉量为100%～140%ET0时单果重、果肉率最高;100%ET0时产果量最高;40%ET0时含油率最高;80%ET0时产油量最高。对于果用油橄榄最佳灌溉量范围为100%～140%ET0,油用油橄榄最佳灌溉范围为60%～100%ET0。     

银杏品种耐盐能力的研究

我国沿海是一个自然资源宝库 ,土地面积大 ,发展林业的潜力很大。要在这些地区建立和培育各种不同功能的人工林 (防护林、水土保持林、风景林及速生丰产林等 ) ,关键在于选择适宜于该立地条件生长的耐盐树种。近年来开展植物抗盐生理的研究已取得明显的进展 ,在植物耐盐机理、耐盐细胞系的培育、渗透调节基因的转移、野生植物抗盐基因的利用、盐生植物的开发以及利用生长调节剂来提高植物的耐盐性等方面获得了可喜的成果 (Crameretal.,1 986;刘友良等 ,1 987;John ,1 988;Gorham ,1 985 ;赵可夫等 ,1 989;沈惠娟 ,1 993)。但是对植物耐盐…     

沙棘林改土培肥作用的研究

通过对沙棘林土壤及枯枝落叶营养状况的测定,结果表明,不同地区、不同林龄沙棘林地土壤和枯枝落叶营养元素含量差异不大,林地土壤中N全、P全、K全、Ca++、Mg++的含量分别为O.0306%-O.2902%、O.0843%-O.1779%、2.1274%-2.8207%,0.0026%-0.0182%、1.3375%×10-4-6.9385%×10-4;N速、P速、K速、CEC值分别为15.167%-52.267%、2.5747%-l4.l980%、78.8735%-33.4135%、8.1860-25.2595mg/kg。枯枝落叶的N全、P全、K全、Ca++、Mg++分别为1.2696%-11.6694%、0.0576%-0.1283%、0.6250%-0.9823%,2.0643%-3.8821%、0.2187%-0.3143%,且不同土层和林龄表现出不同的规律性;沙棘林地土壤中有机质与N、P、K相关性最为密切。沙棘林地营养含量比相应的农田和草地的高得多,表现出明显的改土培肥作用。     

Estimation of the self-thinning boundary line within even-aged Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) stands: Onset of self-thinning

The trajectory of self-thinning was studied using data from Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) stands measured 17 times over 26 years to elucidate the relationship between the maximum average stem volume (dm³) and the stand density (stems/ha). The study examined five initial density levels (2 m × 3 m, 2 m × 1.5 m, 2 m × 1 m, 1 m × 1.5 m, and 1 m × 1 m) with three replications at each level, but only 10 plots were used in the final analysis. Subsets of the data were constructed using 0-67%, 2-67%, 5-67%, 10-67%, 15-67%, 20-67%, 23-67%, 25-67% and 30-67% mortality rate classes. Ordinary least squares and reduced major axis (RMA) regression techniques were employed to obtain self-thinning parameters for each mortality rate class subset. The RMA method combined with jackknife estimation (RMA + jackknife) was the most appropriate regression method based on standard error estimations. The self-thinning exponent with a mortality rate class of 2-67% adequately represented the maximum volume-density relationship. The self-thinning exponents changed systematically with the mortality rate classes, and −1.5 was a transitory value in the course of self-thinning. It is also concluded that self-thinning in closed Chinese fir stands may occur when the ratio of the live crown length to tree height approaches 0.3.     

四种算法用于近红外测定制浆材材性的对比研究

采集了常见制浆材(桉木、相思木及杨木)样品的近红外光谱,测定了样品的基本密度、综纤维素、木质素和苯醇抽出物含量,用人为控制水分的方法测定了样品的水分含量。对原始光谱进行预处理后,分别运用偏最小二乘法(PLS)、LASSO算法、支持向量机法(SVR)和人工神经网络法(BP-ANN)建立基本密度、水分含量、综纤维素、木质素和苯醇抽出物含量的预测模型。对预测模型进行独立验证,结果显示:LASSO算法建立的基本密度和综纤维素模型性能最优,其预测均方根误差(RMSEP)分别为0.006 3 g/cm~3和0.49%,绝对偏差(AD)范围分别为-0.008 8~0.009 6 g/cm~3和-0.85%~0.87%;PLS建立的水分含量模型及苯醇抽出物模型最优,RMSEP值分别为1.21%和0.24%,AD范围分别为-1.99%~2.03%和-0.35%~0.38%;SVR建立的木质素模型最优,RMSEP值为0.43%,AD范围为-0.76%~0.74%,均满足制浆造纸工业中对误差的要求。     

Carbon concentration variability of 10 Chinese temperate tree species

A mass-based carbon (C) concentration ([C]) of 50% in dry wood is widely accepted as a constant factor for conversion of biomass to C stock. However, the [C] varies with tree species, and few data on [C] are available for the Chinese temperate tree species. In this study, we examined inter- and intra-specific variations of [C] in biomass tissues for 10 co-occurring temperate tree species in northeastern China. The species were Korean pine (Pinus koraiensis Sieb. et Zucc.), Dahurian larch (Larix gmelinii Rupr.), Mongolian oak (Quercus mongolica Fisch.), white birch (Betula platyphylla Suk.), Amur cork-tree (Phellodendron amurense Rupr.), Manchurian walnut (Juglans mandshurica Maxim.), Manchurian ash (Fraxinus mandshurica Rupr.), aspen (Populous davidiana Dode), Mono maple (Acer mono Maxim.), and Amur linden (Tilia amurensis Rupr.). The mean tissue [C] across the species varied from 47.1% in fine root to 51.4% in foliage. The mean stem [C] of the 10 species was 49.9 ± 1.3% (mean ± SE). The weighted mean C concentration (WMCC) for the species ranked as: Amur cork-tree (55.1%) > Amur linden (53.9%) > Korean pine (53.2%) > Manchurian ash (52.9%) > Manchurian walnut (52.4%) > Mongolian oak (47.6%) > Dahurian larch (46.9%) > Mono maple (46.4%) > white birch (46.1%) > aspen (43.7%). The WMCC of the dominant trees was negatively correlated to mean annual increment of biomass (MAI), suggesting that planting fast-growing tree species for C sequestration in afforestation and reforestation practices sacrifice some C gain from increasing MAI due to decreasing [C]. Failing to account for the inter- and intra-specific variations in [C] will introduce a relative error of −6.7% to +7.2% in estimates of biomass C stock from inventory data, of which >93% is attributed to ignoring the inter-specific variation in [C].     

Comparison of 5th- and 14th-year Douglas-fir and understory vegetation responses to selective vegetation removal

The effects of early vegetation management on the survival and growth of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] were examined 5 and 15 years after planting in the Oregon Coast Range. Our first objective was to document the effects of vegetation species competition upon key ecosystem properties. The second objective was to document the effects of vegetation removal during early Douglas-fir stand establishment upon long-term tree growth and on biomass production by vegetation components. Seven levels of manual vegetation removal were maintained for the first 5 years after planting: 0%, 25%, 50%, 75%, and 100% shrub removal; and 100% shrub removal combined with 50% or 100% herbaceous vegetation removal. Shrub and herb removal did not affect Douglas-fir survival at year five, but treatments providing less than 75% shrub removal significantly reduced Douglas-fir survival by year 15. Removing shrubs and herbs completely (100S + 100H) during the 5 years following tree planting allowed successful tree establishment, with a 366% increase in biomass accumulation per hectare for Douglas-fir in that treatment at the end of 14 years of growth. At 15 years stand age, even with shrub removal alone, a 304% gain in tree biomass per hectare was obtained compared to no vegetation removal (NVR). By stand age 15 years, any increase in the degree of understory removal beyond 75% did not contribute significantly to additional tree survival and growth. The understory vegetation on NVR treatment plots and the herbaceous vegetation on 100% shrub removal (100S) treatment plots, contained >90% and >80% of aboveground biomass N at 5 years, respectively, indicating possible competition for soil N. Soil moisture was not different among treatments at 5 years. Complete vegetation removal (100S + 100H) for 5 years resulted in a significant increase in soil bulk density (P < 0.05), a significant decrease in total soil C (P < 0.05) and no change in total soil N in the upper 15 cm of the mineral soil. By 14 years, however, only the soil bulk density remained greater (P < 0.05) on the 100S + 100H treatment. We conclude that greater tree survival and growth occurred with at least 75% shrub removal. Our results suggest that managers may have substantial flexibility in maintaining a partial understory component suitable for ecosystem productivity, canopy cover and wildlife habitat, while maintaining forests productive for timber resources.     

Stocks and decay dynamics of above- and belowground coarse woody debris in managed Sitka spruce forests in Ireland

Coarse woody debris (CWD) has become recognised as an important component of the carbon (C) pool in forest ecosystems. In Ireland, managed Sitka spruce (Picea sitchensis (Bong) Carr.) forests account for 52.3% of the total forest estate. To determine the stock and decay dynamics of above and belowground CWD, field surveys using fixed area sample plots, were conducted in six even-aged Sitka spruce stands, representing the young, intermediate and mature stages of a typical commercial rotation. The volume, mass, density loss and C:N ratio of all CWD types (logs, stumps, and coarse roots) were determined using a five-decay class (DC) system. The decay rates and half life of CWD was also determined. To estimate CWD coarse root mass; roots associated with stumps classified in different decay classes were excavated. The coarse roots were categorised into small (2-10 mm), medium (10-50 mm) and large (>50 mm) diameter classes.CWD C-mass ranged from 6.98 to 18.62 Mg ha⁻¹ and was highest in an intermediate forest (D35), while the aboveground volume varied from 6.31 to 42.27 m³ ha⁻¹. Coarse roots accounted for 21% to 85% of the total CWD C-pool in the surveyed stands. The total CWD C-mass was poorly correlated with the number of thinning events (R² = 0.29), when data from D35 was excluded. The density loss was significant in logs (45%), stumps (58%), and small- (38%), medium- (50%) and large roots (38%) as decay progress from DC 0 to 4. There was a 46%, 41%, 51%, 72% and 57% decline in C:N ratio of logs, stumps, small-, medium- and large roots, respectively, as decay progressed from DC 0 to 4. The density decay rates were 0.059, 0.048 and 0.036 kg m⁻³ year⁻¹ for logs, stumps and coarse roots, respectively. The size classification of roots did not significantly affect their decay rate. The half life (50% decomposition) of CWD was estimated has 12-, 14- and 19 years for logs, stumps and roots of Sitka spruce. Regression curves showed a strong correlation between the density and C:N ratio (R² = 0.69, 0.74 and 0.93 for logs, stumps and coarse roots, respectively). The long term storage of C and its slow rate of decomposition make CWD a vital structural and functional component of the CWD C-pool and a major controller of forest ecosystem C-retention.     

计算机配色应用于木材染色领域的初步研究

采用计算机配色技术,确定用于仿紫檀木材染色的染料配方,从而对计算机配色技术在木材染色领域的应用进行初步研究,对其应用前景进行探讨。最终确定的仿紫檀木材染色的染料配方为：活性艳红0．116％;活性黄0．219％;活性蓝0。032％;助剂A2％;助剂B2％。     

雷公藤总甙对马尾松毛虫生物活性的影响

以无水乙醇为溶剂,用连续回流渗漉法从雷公藤生药中提取出粗提物。经乙酸乙酯纯化后得红褐色的浸膏,经检测为总萜内酯（T1）。就其杀虫活性和作用方式进行了较系统的生物测定。结果表明：T1对马尾松毛虫具有强的拒食、麻醉和毒杀作用,毒杀中浓度LC50为1548．50mg／L,拒食中量AFD50为12．25μg／条,麻醉中量ND50为103．98μg／g,无触杀作用;T1不仅抑制马尾松毛虫幼虫的生长发育．还影响其蛹的羽化和卵的孵化及初孵幼虫存活;抑制中浓度EC50为952．65mg／L;在T1浓度10～10000mg／L之间,马尾松毛虫蛹不完全羽化率为43．3％～63．3％。其卵的不能孵化率为12．0％～84．0％,孵化的幼虫存活率为0．0％～95．6％。