修枝处理对杨—麦复合模式内小麦产量和品质的影响

以杨—麦复合模式及小麦单作模式为研究对象,设计了4种修枝处理,比较不同修枝处理内小气候因子、小麦产量及品质的差异,并分析影响小麦产量及品质的主要小气候因子。结果表明:杨—麦复合模式内小麦穗长、单穗重、麦粒长、千粒重及产量均显著低于对照模式,但小麦营养成分含量表现不一;对杨—麦复合模式内欧美杨107进行不同修枝处理后,处理Ⅰ内小麦产量及品质要好于其他3种修枝处理。可见,小麦产量及品质随杨—麦复合模式内小气候因子的改变而发生变化,而小气候因子的变化与杨树修枝强度与方法密切相关。因此,为实现杨树与农作物"双赢",应采用处理Ⅰ的修枝方法开展杨树修枝,即从造林第5年春季修除第1年生的轮生枝,第6年春季修除第2年生的轮生枝。     

修枝起始年龄和季节对Ⅰ-69杨修枝口愈合的影响

对2007年春营造的Ⅰ-69杨进行了不同修枝处理,探讨了修枝起始年龄、修枝季节对修枝口愈合的影响。结果表明:Ⅰ-69杨修枝口(宽度W)越小,其完全愈合所需时间越短,完全愈合率也越高,宽度W<4 cm修枝口的完全愈合率明显大于W≥4 cm修枝口。修枝口愈合受到修枝枝龄的影响,随着枝龄的增长,较大修枝口所占比重增大,死枝修枝口数量也增多,修枝口的完全愈合率和愈合生长率均下降。修枝口愈合也受到修枝季节的影响,与冬季、夏季修枝相比,春季修枝的完全愈合率、愈合生长率明显较高。综合考虑修枝对杨树胸径生长量的影响,笔者认为Ⅰ-69杨的修枝起始年龄以第1轮枝条的年龄达到4年时为宜,修枝季节以春季(3月下旬至4月上旬)为宜。     

杨树修枝新技术与新工具

笔者对杨树修枝方面没有取得突破性进展的因素进行分析:一是林业技术人员和农民对杨树修枝的原理和重要意义认识不足;二是对现有的修枝方法——以冠高比指标确定修除的枝条、以枝条着生处的主干直径指标确定修除的枝条或者以枝条基部直径指标确定修除的枝条难以准确把握;三是传统的搭梯上树修枝方法具有不安全性和低效性。本文阐述了杨树修枝的原理及科学修枝的意义,对目前杨树修枝存在的突出问题提出了新的定量修枝方法:第1～4年只修除重生的主干与"卡脖子"大枝;第5～7(8)年每年从下往上修除一轮枝条,同时应用日本进口的新的修枝工具——伸缩式高枝锯,实现了修枝的安全性,高质量,高效率。     

杨树幼林的修枝

我们打火店林场,目前约有杨树幼林6,000余亩,一般树龄3-12年生。近几年来,我们进行了人工修枝,收到了良好效果。如马家沟管区6年生的杨树幼林,经过人工修枝后,年平均高生长量一般为50-77厘米,胸径生长量为0.55厘米,主干端直,轮生枝层次明晰,顶芽生长快;而未经修枝的幼树年平均高生长量仅为33-59厘米,胸径年平均生长量为0.39厘米,有些树形成灌丛状。     

修枝对欧美杨107杨水分生理的影响

以欧美107杨为研究对象,从树干液流、蒸腾速率(Tr)以及叶水势(LWP)等杨树水分生理指标角度,探讨修枝处理对这些生理指标在生长季(6—9月)内的影响及其变化规律,并做相应的分析和讨论。试验地Ⅰ以4年生107杨为样木,试验地Ⅱ以6年生107杨为样木。试验地Ⅰ,Ⅱ均设计3个处理组,每个处理组设有3种处理,即对照处理CK(不修枝)、中度处理P1(修掉树冠高度的1/3)、重度修枝P2(修掉树冠高度的2/3)。研究结果表明:1)发生旱情季节(6—8月),液流通量及液流速率呈现P1>CK>P2的规律;正常月份(9月),液流通量及液流速率呈现出CK>P1>P2的规律;P1的液流通量及速率在旱季或正常月份大小基本相同。这表明同正常月份未修枝CK相比,适当修枝(P1)使杨树树干液流始终保持在一定的较低水平,抗旱能力得到一定程度的提高。2)整个生长季内,蒸腾速率(Tr)和叶水势(LWP)都呈现出CK相似文献   

豫东平原3种模式杨树-小麦复合系统水分利用效率的研究

农林复合系统的林木和作物会充分利用水肥光热等资源,但搭配不合理也可能产生资源竞争,其中,种间水分竞争尤为突出。本文在冬小麦4个生育期内采用稳定碳同位素技术研究了豫东平原2年生、6年生和15年生3个间作模式的杨树-小麦复合系统的水分利用状况。结果表明:3种间作模式杨树和小麦的δ¹³C(稳定碳同位素比率)和WUE(水分利用效率)均总体表现为小麦拔节期最高。在整个小麦生育期(拔节期除外),2年生杨树的δ¹³C和WUE都显著高于6年生和15年生杨树。在小麦返青期,相比其他模式,2年生杨树间作小麦的δ¹³C和WUE最高;在拔节期、开花期和成熟期则均为单作小麦显著高于3种间作模式小麦。单作小麦的耗水量比与2年生杨树间作的小麦低25.71%,但分别是与6年生和15年生杨树间作小麦耗水量的2.78和1.88倍。3种林龄杨树-小麦间作模式总体都表现为树行中间和西侧的小麦WUE和耗水量大于树行东侧。2年生杨树间作小麦的株高、LMA(比叶重)、产量、总生物量、总耗水量和LER(土地当量)均高于单作小麦和其他模式间作小麦;但单作小麦的千粒质量、收获指数和产量水分利用效率则最大。2年生杨树-小麦间作模式的产量和土地利用率最高,但随着杨树的长大,间作模式内不再适合种植小麦,可替代种植一些耐荫作物。     

杨稻复合系统的胁地因子分析

通过对江苏省泗洪县城头林场2 a、3 a和4 a生杨树与水稻复合经营模式下的小气候因子以及水稻产量的测定分析知,水稻产量随着林龄、冠幅、树高增加而减少,随着日照时数、光合速率的增加而增加.林木树高是影响林带内水稻产量的最主要影响因子.     

江汉平原典型杨－农复合经营模式及效益分析

通过连续3年试验监测,对江汉平原5种典型杨-农复合经营模式及效益进行了分析.结果表明：杨树幼林农林间作不仅能促进杨树生长,还可以获得明显经济效益.不同间作模式收益及影响杨树生长有差异,综合效益较好的模式有：杨树＋西瓜＋小麦、杨树＋棉花＋小麦和杨树＋玉米＋小麦.     

不同修枝强度对杨树生长的短期影响

以4年生欧美I-107杨为研究对象,首先测定了不同层次叶片的净光合速率,然后针对性地研究了P1(修掉冠长的1/5)、P2(修掉冠长的2/5)、P3(修掉冠长的3/5)以及不修枝(CK)等处理对杨树胸径、树高、材积及相对削度增量的影响。结果表明:随着冠层高度的上升,杨树叶片的净光合速率逐渐增大,呈明显的分层性。修枝后第3年,P1处理的胸径和树高增量均最大,其中胸径增量显著高于其它处理,而树高增量与其它处理差异不显著;同时P1处理的材积亦是最大,分别比P2、P3和CK增加10.34%、33.33%和23.08%,差异达显著水平。此外,随着树干高度的上升,各修枝措施均有效地提高了原木相对削度的增量,减小了树干尖削度,使得树干通直饱满,从而提高了出材率。综合分析认为,P1修剪措施对4年生杨树的作用效果最佳。     

杨-粮间作新栽培模式对小麦产量及质量影响的评价

主要探讨了杨－粮间作新栽培模式对小麦产量和质量的影响。研究结果表明：５年生杨树杨－粮间作新栽培模式小麦产量低于对照农田１０％￣１５％、林内小麦种子的淀粉含量和蛋白质量均高于对照农田。分别增加了１２％和２２．１％,蛋白质提高幅度大于淀粉提高幅度。影响小麦产量和千粒重的主要因子为照度,空气温度、空气湿度及土壤含水量;提高小麦质量的主要因子为空气温度。     

杨-小麦复合经营模式的立地生产力及生态经济效益评价

根据目前平原农区经济发展的现状和林木生长的边行优势原理 ,设计了 6种双行大间距的杨农复合经营模式。试验点位于江苏省宝应县 ,于 1992年春植苗造林 ,供试杨树品种为NL - 80 35 1,农作物品种为小麦 ,6种杨树配置模式分别为Ⅰ :(3× 3)× 2 0m ;Ⅱ :(3× 3)× 30m ;Ⅲ :(3× 3)× 4 0m ;Ⅳ :(4× 4 )× 2 0m ;Ⅴ :(4× 4 )× 30m ;Ⅵ :(4× 4 )× 4 0m。根据调查研究的资料 ,本文主要探讨了小麦不同物候期内不同杨农复合经营模式中小气候条件的时空变异 ,不同模式对农作物产量和质量的影响 ,生物生产力及光能利用率的差异及其经济效益评价。研究结果表明 :(1)杨农复合经营模式降低了作物面层上的太阳总辐射和温度 ,提高了作物面层上的相对湿度。与单农经营相比 ,不同复合模式及不同物候期内太阳总辐射和光照强度降低了 3 9%～ 36 2 % ,相对湿度提高了 2 5 %～ 3 9%。(2 )杨农复合经营对小麦的产量和质量有较大影响。与单农经营相比 ,小麦千粒重和单位面积产量均有所下降 ,但不同间作模式下降的幅度存在较大差异 ,而小麦中淀粉含量和蛋白质含量均明显高于单农经营 ,平均分别高12 1%和 18 3%。 (3)林分 7年生时 ,6种杨粮 (小麦 )间作模式的生物生产力、光能利用率和经济效益均高于单农经营 ,其大小顺     

梯田堰边老龄低产花椒树更新改造研究

以梯田堰边老龄低产花椒为试材,采用随机区组设计进行不同修剪试验。发现刻芽、中截、重截、疏枝修剪处理均能促进新梢生长,提高叶绿素含量,显著提高花椒单株产量、穗重,增加花椒出皮率。以疏枝处理对花椒新梢生长、果实产量品质影响最显著。平茬更新处理的花椒树的叶色浓绿、叶片肥厚、生长壮旺,果实产量和枝量明显高于对照树,复壮效果明显。     

Biomass dynamics of Erythrina lanceolata as influenced by shoot-pruning intensity in Costa Rica

Pruning of agroforestry trees, while reducing shade of the crops, usually reduces both biomass production and nitrogen fixation. Short pruning cycles are often not sustainable on the long run, because tree production declines over subsequent pruning cycles. We compared biomass and labile carbohydrate dynamics of Erythrina lanceolata Standley (Papilionaceae) shade trees under total and partial pruning regimes in a vanilla (Vanilla planifolia L.) plantation in South-western Costa Rica. The highest biomass production was measured in the unpruned control, followed by trees with 50% of the leaf pruned every three months, while total pruning every six months resulted in the lowest biomass pruduction. In the more productive treatments, a higher proportion of the production was in branches. Because, the N content of woody branches was high, they were important for nitrogen cycling. In the partial pruning treatment more nitrogen was returned to the soil from litter and woody branches than from pruned leaf. Sugar concentrations were not different between treatments and the dynamics of non-structural carbohydrates (sugar and starch) seems to depend more on plant phenology than pruning treatment. However, the starch concentrations in the total pruning were lower than in the other treatments.This revised version was published online in November 2005 with corrections to the Cover Date.     

Yield components and phenology of durum wheat in a Mediterranean alley-cropping system

It is often claimed that agroforestry could increase the total productivity per land unit compared to monocropping systems. The aim of this study was to evaluate, in a sub-humid Mediterranean climate, the behavior of the yield components, phenology, LAI and NDVI of durum wheat in an alley-cropping system. Our hypothesis was that the microclimate changes in agroforestry could change the devlelopment and yield of cereals. Two different experiments were carried out: in 2015 under 16-year old poplars in East–West lines and in 2016 under 21-year-old ash trees in North–South lines. In each experiment, 12 genotypes of durum wheat were sown. The grain yield was not significantly different in agroforestry and full sun conditions in 2015; however, both systems in this experiment had a particularly low yield (≈ 10% of the historical average yield of the plot). In 2016, the grain yield was significantly lower in agroforestry in comparison with full sun conditions. In both experiments, the most impacted yield component by agroforestry was the number of grains per spike. Similarly, in both experiments, the number of grains per spike was the only yield component impacted by the position within the alley inside agroforestry. Surprisingly, in 2016 the grain yield was higher in the West than in the center position of the alley. In both experiments, agroforestry delayed the maturity of the crop. The use of standard growing degree days was not sufficient to explain the difference in phenology between agroforestry and full sun conditions.     

Dynamics of nonstructural carbohydrates and biomass yield in a fodder legume tree at different harvest intensities

Tropical tree fodder is harvested by frequent prunings, and resprouting depends on nonstructural carbohydrate reserves in the remaining tree parts. We studied the effects of three pruning intensities (removal of all leaves and branches leaving 1 m of stem once a year (T-12), or every 6 months (T-6), and about 50% pruning every 2 months (P-2)) on regrowth and the dynamics of soluble sugars and starch in the legume tree Gliricidia sepium (Jacq.) Walp. growing under humid tropical conditions in Guadeloupe, Lesser Antilles. Carbohydrates were sampled in roots, stems and branches. Among pruned trees, trees in the T-6 harvest regime had the highest leaf fodder yield (0.73 kg tree(-1) year(-1)). High litter loss reduced leaf yield of T-12 trees, but compared with the other treatments, T-12 trees produced the most branch biomass (3.43 kg tree(-1)). Among treatments, P-2 trees had an intermediate leaf fodder yield and the lowest branch production. Sucrose, glucose and fructose were the most common sugars in all biomass compartments. Mannose, pinitol and an unidentified cyclitol were relatively abundant in branches. Root sugar and starch concentrations were unaffected by harvest regime. There was a significant interactive effect of harvest intensity and regrowth time on stem sugar concentration. Stem starch concentration was highest in T-12 trees. After a year of fodder harvesting, whole-tree reserves of nonstructural carbohydrates were highest in T-12 trees; however, a larger proportion of reserves were located in roots and stems of T-6 and P-2 trees. These reserves, which were not lost in pruning and contributed to regrowth of G. sepium after pruning, may explain the relatively small effects of harvesting regime on soluble sugar and starch concentrations.     

截干对红松人工幼龄林侧枝生长的影响

以红松人工幼龄林(10年生)为研究对象,开展不同截干处理的结果表明,红松截干(按比例、轮枝)对侧枝生长影响显著。1/3截干轮枝基径、轮枝长平均值最大值(11.08、1.022)分别比对照高出140.87%、354.22%;三轮截干轮枝基径、轮枝长平均值最大值(8.11、0.51)比对照高出298.52%、211%。1/3截干平均值(11.08、1.022)比三轮平均值(8.11、0.51)要大,1/3截干最好。     

稀土对杨树杂交种子数量和品质影响的初步研究

稀土元素从镧到镥(La—Lu,原子序数57—71)是元素周期表ⅢB族成员。它们在植物中的分布和作用国外很早就有研究,1878年Cossa就报道了(木菊)材、烟草、葡萄等植物中含有少量稀土。我国对稀土的研究起步较晚,农业方面的应用有十几年的历史,在小麦、水稻、苹果等主要作物上使用一般可增产8—10％、林业方面的应用只有几年的历史,稀土可以促进插条生根及苗木生长。但对于稀土在树木种子产量和品质方面的作用报道尚不多见,于是我们选择了适宜室内杂交的杨树为材料,利用稀土元素处理杨树切枝母本,对其杂交种子的数量和品质进行了初步研究。     

Commercial pole production in linear agroforestry systems

While the stems of upperstorey trees in agroforestry systems have many uses such as firewood and fencing, it remains true that one incentive for growing upperstorey trees is the anticipated income generated by selling commercial quality poles. Three hundred and ninety-one poles representing 15 tree species grown under linear agroforestry conditions at four sites in Uganda were analyzed in terms of the length, diameter and taper of their poles. At the time of harvest, the trees were 41 months old. Although the poles varied in size and shape, none conformed to the standards observed in the commercial pole market in Kampala. The results demonstrate that linear agroforestry systems are unlikely to produce high quality commercial poles in a short time although they have other uses. Development of commercial pole production in these systems requires low cost management practices. New research designs and hypotheses are needed to assess the potential of commercial pole production. They must consider trials with larger plots, longer duration and varying management practices such as side pruning, spacing, coppicing and pollarding.     

苹果改良纺锤形树形整形修剪技术研究

对当年定植的苹果幼树刻芽定干，提高了整形带内的萌芽率和发枝率，以刻3芽和刻4芽效果最好。作小主枝缓放处理的1a生枝在基部刻枝条的侧芽、背下芽，在刻芽数占总芽数的1／5、1／3、2／3等3个处理中，随刻芽数增加萌芽率提高，以刻2／3芽的处理萌芽率最高，达91.1%；作小主枝的1m以下的1a生枝极重短截，可极明显地促发壮枝，年生长量可达145.7cm;小主枝基产重环剥可控制旺梢生长,利于花芽分化,提高成花率;对基部小主枝的侧生分枝拉枝、刻芽，可提高萌芽率和中、短枝比例。采用改良纺锤形整形的乔砧矮化密植2001苹果，栽后第2年见花，第3年就有一定产量，第4年进入初结果期，单株产量可达32.8kg。     

金丝小枣老树修剪强度的研究

１９９６－１９９９年在山东省乐陵枣－粮间作地区对约６０年生的金丝小枣树进行了修剪试验,研究表明,修剪是使老枣树更新复壮、恢复产量的重要措施,修剪强度以轻剪为宜。结果基枝以保留４个枣股的结果密度最大（１．４７）,较对照（０．７６）增加９３％,与留８个枣股及对照的差异显著,与留２个枣股的差异极显著。增加叶面积约２０％,叶绿素含量约增加１３．３６％,空吊数约减少３４％。