湿地松施肥效果试验阶段初报

以湿地松容器苗当年造林地进行施肥试验,结果表明:湿地松施肥当年主要促进地径生长,第2—4年地径、树高增长作用明显;施肥以复合肥效果最好;施肥量与林木生长呈正相关;合理施肥量为75g/株.     

旱冬瓜山地造林施肥试验

2009年7月采用随机区组试验设计进行旱冬瓜山地造林施肥试验,2011年1月进行旱冬瓜幼林高、径生长量调查,分析结果表明:进行山地造林时施底肥能显著促进旱冬瓜幼林的高、径生长,施肥幼林高生长高出对照43.5%,径生长高出对照92.7%;以施N肥的作用最为显著,尤以150 g表现最好,林木的高、径平均生长量分别高出对照85.2%和165%.     

毛红椿和杉木混交幼林对不同施肥措施的生长响应

于2020—2021年,在福建省顺昌埔上国有林场连续2 a开展毛红椿和杉木混交幼林施肥试验,探讨不同肥料类型及施肥量等对毛红椿和杉木混交幼林生长量的影响。结果表明：施肥处理的林分地径、树高、当年抽高,1年生时分别比对照增加26.18%、7.25%、62.5%,2年生时分别比对照增加12.83%、19.62%、28.09%。同一施肥类型不同施肥量对毛红椿和杉木混交幼林生长表现的影响,总体上随着施肥用量的增加,混交幼林的地径、树高、当年抽高均呈现增加趋势。施用不同肥料类型对毛红椿和杉木混交幼林生长影响排序为混合肥>复合肥>有机肥。方差分析表明,1年生时,地径在不同重复间和不同处理间的差异均达极显著水平,在重复和处理互作效应的差异达显著水平;树高在不同重复间的差异达极显著水平,而在不同处理间的差异不显著;当年抽高在重复间和处理间的差异均达极显著水平。2年生时,地径和当年抽高在不同处理间的差异均达显著水平;树高在不同处理间的差异均达极显著水平,而在不同重复间的差异均不显著。经过2 a的施肥试验表明,毛红椿和杉木混交幼林施肥方案以混合肥且施肥量150 g·株^-1...     

氮磷钾配比施肥对三尖杉幼林生长的影响

利用2006年春栽植在浙江省淳安县富溪林场龙门里苗圃的三尖杉1年生苗和2年生苗营造的幼林分别开展施肥实验,施肥处理采用3因素4水平正交设计,结果表明,在土壤肥力中下,N、P及有机质含量稍低的情况下. N、P、K适当配比施肥能显著促进三尖杉生长,但过量施肥,则会抑制其生长.N、P、K不同配比施肥对三尖杉幼林生长的影响差异显著,当年抽梢长度、当年地径年生长量、次年抽梢长度、次年地径年生长量和次年分枝数指标,蒯9巴处理的1年生苗造林幼林分别比不蒯吧的对照高23.51%、25.00%、50.05%、28.79%和22.67%,2年生苗造林幼林则分别比不施肥的对照高60.10%、7.41%、18.50%、55.39%、41.67%和8.94%.多数生长性状的N×P互作效应显著,配比施用N、P能显著促进三尖杉幼林生长.根据抽梢长度和地径生长量指标得出的三尖杉幼林最佳N、P2O5和K2O的配比蒯吧量为6.0、6.0和1.5 g,株.     

不同树种在高海拔山地造林中的生长表现

对永春县高海拔山地9年生柳杉×木荷混交林补植火炬松、马尾松4年后的生长数据进行调查,结果表明:4年生火炬松的地径生长与13年生柳杉已无显著差异,树高已显著高于13年生柳杉,远大于木荷,与马尾松相比,同林龄火炬松的树高和地径生长均显著大于马尾松。补植造林后,林分蓄积量得到了显著提高。可见,在高海拔特殊立地条件下,火炬松可用来作为快速绿化的先锋树种,造林成效显著。     

火炬松、湿地松容器育苗与造林

几年来,由于推广、应用了温床育苗芽苗移栽新方法,火炬松、湿地松的大田育苗每公斤种子产苗量达2万株以上.但如何提高火炬松、湿地松造林的成活率,特别是遇到春夏连续干旱的情况,保证一次造林成功,尚无有效的方法.为了解决这个问题,1984年我们在省林科所指导下进行了火炬松、湿地松容器育苗,共育苗20万株.苗木生长良好,平均高20厘米,平均地径0.46厘米,并在7—9月的雨季利用这些苗木对新造林地进行了补植,共补植苗木3万多株,成活率达99%以上,获得了满意的效果.现将有关技术介绍如下:     

白榆的袋接法

白榆是我区主要造林树种之一,培育苗木的常规方法是播种育苗,所培育的苗木生长缓慢。采用嫁接方法所培育的白榆苗木生长极快。据调查:当年生嫁接苗的高生长达3.5米,地径达3.2厘米;二年生嫁接苗高生长达4.2米,地径可达6.6厘米。而当年生实生苗高生长仅为0.56米,地径仅为0.69厘米;二年生实生苗高生长为1.30米,地径为1.3     

火炬松造林技术措施的关联序分析

用湖南湘中地区８７块标准地材料，应用关联序分析法对火炬松造林技术措施进行因素分析表明：影响火炬松胸径生长的主要因素是苗木规格和立地条件，其次为施肥的作用，整地和抚育的作用居第三位。影响火炬松高生长的主要因素是苗木规格和立地条件，其次是整地、抚育、施肥的作用居第三位。该结果在生产上具有极为重要的指导意义。     

不同施肥处理对造林用红豆树幼苗高、径生长的影响

2019年3月,在浙江省温岭市采用1年生和2年生红豆树Ormosia hosiei实生苗造林,幼苗分别为地径2 cm带土球及营养钵苗、地径4 cm带土球截顶苗和全冠苗,于2019年10月测定苗木的高度、地径,分析不同试验处理(苗木规格、苗木类型、截干方式、施肥处理)对红豆树当年生幼树生长的影响。结果表明,在相同施肥措施下,地径2 cm幼苗适宜带土球种植,地径4 cm带土球幼苗进行截顶造林更利于植株的生长发育;不同施肥处理间也有较大差异,除地径2 cm营养钵幼苗施用菌根肥和混合施用菌根肥加30 g·株^-1复合肥表现出较明显受抑制生长外,其余各施肥处理对红豆树苗的生长均有不同程度的促进作用,其中以地径2 cm营养钵苗和地径2 cm带土球苗施用30 g·株^-1复合肥、地径4 cm带土球截顶苗施用50 g·株^-1复合肥生长效果明显高于其他施肥处理。选择高生长量、地径生长量、高径比和造林成本4项指标,采用模糊隶属函数法对红豆树苗不同处理条件下的综合效益进行综合评价,结果表明,红豆树幼苗采用地径2 cm带土球苗并施以30 g·株^-1复合肥的造林综合效益最高。     

枫香苗木短截造林技术

枫香苗木短截与未短截造林对比试验结果表明,其生长量明显提高,造林当年新梢平均高提高了70%,平均地径提高了28%;造林后第4年平均树高提高了37%,平均胸径提高了34%。方差分析表明,造林当年的新稍高、造林后第4年的树高与胸径3个调查项目的枫香苗木短截造林与不短截造林间生长量差异均达到了极显著水平;只有造林当年的地径调查项目生长量差异不显著。     

Leaf traits in relation to crown development, light interception and growth of elite families of loblolly and slash pine

Crown architecture and size influence leaf area distribution within tree crowns and have large effects on the light environment in forest canopies. The use of selected genotypes in combination with silvicultural treatments that optimize site conditions in forest plantations provide both a challenge and an opportunity to study the biological and environmental determinants of forest growth. We investigated tree growth, crown development and leaf traits of two elite families of loblolly pine (Pinus taeda L.) and one family of slash pine (P. elliottii Mill.) at canopy closure. Two contrasting silvicultural treatments -- repeated fertilization and control of competing vegetation (MI treatment), and a single fertilization and control of competing vegetation treatment (C treatment) -- were applied at two experimental sites in the West Gulf Coastal Plain in Texas and Louisiana. At a common tree size (diameter at breast height), loblolly pine trees had longer and wider crowns, and at the plot-level, intercepted a greater fraction of photosynthetic photon flux than slash pine trees. Leaf-level, light-saturated assimilation rates (A(max)) and both mass- and area-based leaf nitrogen (N) decreased, and specific leaf area (SLA) increased with increasing canopy depth. Leaf-trait gradients were steeper in crowns of loblolly pine trees than of slash pine trees for SLA and leaf N, but not for A(max). There were no species differences in A(max), except in mass-based photosynthesis in upper crowns, but the effect of silvicultural treatment on A(max) differed between sites. Across all crown positions, A(max) was correlated with leaf N, but the relationship differed between sites and treatments. Observed patterns of variation in leaf properties within crowns reflected acclimation to developing light gradients in stands with closing canopies. Tree growth was not directly related to A(max), but there was a strong correlation between tree growth and plot-level light interception in both species. Growth efficiency was unaffected by silvicultural treatment. Thus, when coupled with leaf area and light interception at the crown and canopy levels, A(max) provides insight into family and silvicultural effects on tree growth.     

The effect of weed control and fertilization on survival and growth of four pine species in the Virginia Piedmont

The growth response of loblolly pine (Pinus taeda L.), shortleaf pine (Pinus echinata Mill.), Virginia pine (Pinus virginiana Mill.), and white pine (Pinus strobus L.) to weed control and fertilization in the Piedmont of Virginia was assessed. Four different silvicultural treatments were evaluated: (1) check (no treatment); (2) weed control; (3) fertilization; (4) weed control plus fertilization. The weed control treatment included a series of herbicide and mechanical treatments to eliminate competing hardwoods. The fertilizer treatments added N, P, K, and S. Survival and growth was measured annually through age 5. There were significant differences in survival and growth among species. Survival was greatest for loblolly pine, lower in shortleaf and Virginia pine, and lowest in white pine. Fertilization without controlling the competing hardwoods decreased survival in all planted pines due to the increased hardwood competition. Loblolly pine was tallest through the 5-year period, shortleaf and Virginia pine were shorter and white pine was shortest. Silvicultural treatments had no impact on tree height but significantly affected DBH. Weed control increased DBH while fertilization did not. When applied in combination with weed control, there was no additional increase in growth of the pines due to fertilization beyond that from weed control only. Fertilization stimulated the growth of the competing hardwoods which were significantly taller in the fertilized plots.     

14年生火炬松优良家系选择

在福建省漳平五一国有林场,对美国引进的火炬松第1代种子园25个家系试验林进行测定,以湿地松、马尾松为对照。结果表明:火炬松早期生长较易感染松针褐斑病,保存率较低;14年生火炬松家系总体生长优于湿地松、低于马尾松;各家系在树高、胸径和材积等性状上有着显著差异;综合各性状共选择出4个优良家系(21、9、18、13号),14年生树高、胸径和单株材积的平均值分别为12.6 m、20.4 cm、0.1981 m3,比湿地松增长9.2%、25.9%、71.1%,遗传增益达8.9%、24.7%、67.9%。     

Production,allocation, and stemwood growth efficiency of Pinus taeda L. stands in response to 6 years of intensive management

Loblolly pine (Pinus taeda L.) is a highly plastic species with respect to growth responses to forest management. Loblolly pine is the most planted species across the southern United States, a region with the most expansive and intensively managed forest plantations in the world. Management intensity, using tools such as site preparation and fertilization, is increasing greatly in scope over time. To better define to the productive potential of loblolly pine under intensive management, the influence of 6 years of management with weed control (W), weed control plus irrigation (WI), weed control plus irrigation and fertigation (irrigation with a fertilizer solution) (WIF), or weed control plus irrigation, fertigation, and pest control (WIFP) since plantation establishment on stand productivity in loblolly pine was examined. The site is located near Bainbridge, GA (30°48′N latitude and 84°39′W longitude) and is of medium quality (site index=18 m, base age 25). Increasing management intensity greatly accelerated stand development and biomass accumulation. At age 6 total production (above plus belowground) was nearly doubled from 50 to 93 Mg ha⁻¹ in WIFP stands compared to W stands, and standing stem biomass increased from 24 Mg ha⁻¹ in W stands to 48 Mg ha⁻¹ in response to WIFP treatment. Stem current annual increment (CAI) peaked at age 5 in the WIF and WIFP stands at 17–18 Mg ha⁻¹ per year at a basal area between 18 and 21 m² ha⁻¹. Year to year variation in CAI was better explained by previous-year leaf area index (LAI) than current-year LAI. Maximum stemwood production in loblolly pine was achieved through large increases in LAI and small decreases in allocation to woody roots (tap+coarse roots) versus woody shoots (stem+branches) associated with intensive treatments.     

火炬松第3代种源家系引种试验初报

对美德维斯维克公司火炬松第3代优良种源的10个家系在福建省永安市引种3 a的生长状况进行调查,结果表明,MWV-439家系综合表现最好,引种第3年平均保存率达到87%,平均胸径为6.5 cm,平均树高为431 cm;白蚂蚁是危害火炬松第3代种源家系保存率的主要虫害。     

Importance of weed control, fertilization, irrigation, and genetics in slash and loblolly pine early growth on poorly drained spodosols

Research reported here has evaluated interactions of factors limiting the biological potential of slash pine (Pinus elliottii var. elliottii Engelm.) and loblolly pine (P. Taeda L.). Water and nutrients were manipulated by irrigation, weed control, and intensive fertilization. Genetic factors were incorporated as (1) improved loblolly seedlings from a commercial clonal seed orchard and (2) slash seedlings from four fast-growing, open-pollinated seed-orchard clones. Three replications of a 2 × 2 × 2 factorial experiment were established on a Typic Haplaquod soil in northern Florida using four cultural treatments: no treatment (F0H0); weed control (F0H1); fertilizer (F1F0); and combination of weed control and fertilizer (F1H1) for each species. During the first year there were large, sustained responses to all cultural practices. Loblolly and slash pine showed similar growth responses and had a lengthened growing season (60–100 days). Slash pine growth was superior to that of loblolly. Growth responses observed during the first year continued. After 4 years, irrigation had no measurable effect on tree growth. Both pine species responded equally to F1H0 and F0H1, but slash retained a slight edge. Extra nutrients]available via fertilizer, reduced competition, or additional rooting space, increased slash-pine volume index from an average of 2.0 m³ ha⁻¹ (F0H0) to 11.90 and 13.59 m³ ha⁻¹ (F0H1 and F1H0, respectively). The F1H1 treatment produced the largest slash-pine response, diameter at breast height (D_bh) averaged 9.84 cm, height reached 5.02 m, and volume index rose to about 22.94 m³ ha⁻¹. With teh F1H1 treatment, average loblolly-pine height and volume exceeded that of the average slash pine. At age 4, the growth response due to increased nutrient supply was 13–29 times that of the best genetic response within F0H0 trees of the four slash-pine progenies. The best-growing slash-pine family (6–56) exceeded loblolly-pine growth under all four treatments and approximated the vigor shown by slash pine in the southern hemisphere.     

利用Minirhizotron技术监测火炬松新根生长动态

利用Minirhizotron技术 ,研究了位于美国路易斯安那州的 19年生的火炬松新根生长动态。结果表明 ,火炬松新根的根量密度随时间呈增长趋势 ,在生长季末的 1、2月份达到最大。经过林地土壤干旱处理 (通过建立穿透雨隔离系统 ,阻止雨水到达地面 )的树木的根量密度自 9.3cm处 ,随土壤深度增加呈下降趋势 ,未经干旱处理的树木在离土表 80　 10 0cm深处仍有较高的根量密度 ,达 3.4 8　5 .12条·m- 1,是经干旱处理树木对应土壤层次中根量密度的 10多倍。火炬松从 3月份开始发生新根 ,随后迅速增加 ,至 6月份发生最多 ,然后缓慢减少 ,5　 7月的新根发生数占总量的 4 1.8% ,大部分新根发生在离土表 30cm以内的土壤中。 11个月的干旱处理显著地降低火炬松的根量密度 (1 1条·m- 1,未经干旱处理的为 3 2 7条·m- 1)和新根发生数 (5 7条·株- 1,未经干旱处理的为 15 6条·株 - 1) ,干旱处理还可导致新根推迟 1 0　 1.5个月发生。 5a前在土表撒施化肥似乎对新根的发生和生长没有明显影响     

Simulated biomass and soil carbon of loblolly pine and cottonwood plantations across a thermal gradient in southeastern United States

Changes in biomass and soil carbon with nitrogen fertilization were simulated for a 25-year loblolly pine (Pinus taeda) plantation and for three consecutive 7-year short-rotation cottonwood (Populus deltoides) stands. Simulations were conducted for 17 locations in the southeastern United States with mean annual temperatures ranging from 13.1 to 19.4 °C. The LINKAGES stand growth model, modified to include the “RothC” soil C and soil N model, simulated tree growth and soil C status. Nitrogen fertilization significantly increased cumulative cottonwood aboveground biomass in the three rotations from a site average of 106 to 272 Mg/ha in 21 years. The equivalent site averages for loblolly pine showed a significant increase from 176 and 184 Mg/ha in 25 years with fertilization. Location results, compared on the annual sum of daily mean air temperatures above 5.5 °C (growing-degree-days), showed contrasts. Loblolly pine biomass increased whereas cottonwood decreased with increasing growing-degree-days, particularly in cottonwood stands receiving N fertilization. The increment of biomass due to N addition per unit of control biomass (relative response) declined in both plantations with increase in growing-degree-days. Average soil C in loblolly pine stands increased from 24.3 to 40.4 Mg/ha in 25 years and in cottonwood soil C decreased from 14.7 to 13.7 Mg/ha after three 7-year rotations. Soil C did not decrease with increasing growing-degree-days in either plantation type suggesting that global warming may not initially affect soil C. Nitrogen fertilizer increased soil C slightly in cottonwood plantations and had no significant effect on the soil C of loblolly stands.     

Effect of complete competition control and annual fertilization on stem growth and canopy relations for a chronosequence of loblolly pine plantations in the lower coastal plain of Georgia

Stem growth, developmental patterns and canopy relations were measured in a chronosequence of intensively managed loblolly pine stands. The study was located on two distinct sites in the lower coastal plain of Georgia, USA and contained a factorial arrangement of complete control of interspecific competition (W) and annual nitrogen fertilization (F). The W treatment increased growth rate for several years, while the F treatments led to sustained growth increases. The combination of the W and F treatments resulted in more than 180 Mg ha⁻¹ stem biomass production at age 15 which is more than double the production of control treatment. Stem biomass production is continuing to increase through age 15 as indicated by the current annual increment in stem biomass continuing to exceed the mean annual increment in stem biomass. The F treatment decreased wood quality by decreasing whole tree latewood specific gravity from 0.565 to 0.535 and by lengthening the transition from juvenile to mature wood from 4 to 5 years. Increased rates of stem growth in response to cultural treatments were largely mediated by increased leaf area, with strong functional relationships between leaf area index and current annual increment. However, growth efficiency (stem production per unit of leaf area) decreased with stand age. These results indicate that nutrient amendments are necessary for sustaining high rates of stand development on relatively nutrient poor lower coastal plain soils.     

2种国外松与马尾松生长比较

通过对福建闽侯南屿林场火炬松、湿地松及马尾松家系子代测定林连续10 a的跟踪调查分析表明,火炬松家系不仅在胸径、树高及材积上存在极显著差异,而且与湿地松、马尾松的生长量也存在极显著差异;火炬松早期生长明显优于马尾松,但是随着树龄增长,马尾松生长速度明显加快,7年生时生长量超过火炬松家系平均生长量,10年生时超过火炬松最好家系生长量;湿地松生长趋势与火炬松相似,即前期生长比马尾松快,后期生长落后于马尾松,但湿地松早期生长稍落后于火炬松,后期生长优于火炬松。