生长季酿酒葡萄白腐病分生孢子飞散动态

为给葡萄白腐病的流行及预测提供理论依据,通过对生长季酿酒葡萄园空气中葡萄白腐病菌分生孢子逐日、逐小时捕捉,同时记录空气温度、相对湿度等气象数据,对酿酒葡萄白腐病菌分生孢子的飞散动态及其影响因素进行了研究。结果表明,7月至8月为整个生长季中孢子飞散的高峰期,影响孢子飞散的主要气象因素为温度和湿度。一天中孢子飞散的动态是昼少夜多,18：00~8：00孢子飞散量占全天的95.56%,孢子飞散的最高峰为19：00~7：00。一天中各小时段孢子飞散量与相对湿度呈正相关R=0.898 5,P＆lt;0.01;与温度呈负相关R=-0.823 5,P＆lt;0.01。     

幼龄枣树树干液流的动态研究

利用FLGS-TDP插针式植物茎流计,研究了阿克苏市红旗坡农场棉花试验基地中幼龄枣树树干液流的特点及其与环境因子的关系,结果表明:(1)在整个生长季的晴天,枣树树干液流的日变化呈现明显的单峰曲线;液流在10:00迅速上升,在14:00左右达到高峰,17:30又迅速下降;日累计液流为1.43 L/d,白天液流量占全天的91.19%～98.07%,晚上占1.93%～8.81%;由于夜间空气温度的缓慢上升,枣树在夜间有微弱上升液流。(2)4月份液流量最小为7.18 L,7月份最大为29.85 L,4月的累计流量仅为7月的23.96%。(3)生长季液流速率与环境因子逐步回归分析表明,树干液流受环境因子的综合影响,在日变化中大小依次是净辐射、总辐射、空气温度、风速和相对湿度,相关系数为0.68,决定系数为0.48;在季变化中影响大小依次为空气温度、总辐射、净辐射、相对湿度和风速,相关系数和决定系数都是0.89。     

华北土石山区油松生长季夜间液流分配特征

【目的】通过对油松生长季夜间液流特征和环境驱动因素的研究,揭示夜间液流组分拆分特征,探讨夜间液流的组分与气象因子之间的相关关系,以及茎干补水对气象因子的响应,为华北土石山区水资源和水源涵养林管理决策提供理论依据。【方法】以华北土石山区的油松作为研究对象,根据径阶大小选取18棵样树,在2014年生长季运用Granier热扩散探针技术(TDP)持续观测夜间液流,结合称重式蒸渗仪和自制微型蒸渗仪来计算蒸腾量,解析夜间液流的去向;并进行夜间液流与土壤含水量、大气温度、湿度及光合有效辐射等气象因子的相关分析,以确定主要驱动因素。【结果】在6—9月典型晴天,夜间液流速率都呈逐渐降低趋势,18:00—24:00的夜间液流速率高于00:00—05:00,夜间液流主要用于对白天失水过多的茎干进行补水,以至于在24:00时油松茎干储水量基本达到饱和,因此,00:00—05:00夜间液流速率趋于稳定;油松夜间液流用于茎干补水的比例(95.34%)显著高于用于夜间蒸腾量的比例(4.66%);油松夜间茎干补水量与饱和水汽压差呈极显著正相关(R²=0.793, P <0.01),而对土...     

内蒙古大青山华北落叶松成熟林生长季土壤呼吸研究

以内蒙古大青山华北落叶松成熟林为研究对象,对生长季林地土壤呼吸速率及土壤温度、湿度进行定位监测,分析了土壤呼吸速率变化特征与土壤水热因子之间的相互作用规律。结果表明:(1)林地土壤呼吸速率有明显的季节动态变化和日变化规律。生长季5～9月土壤呼吸速率大小表现为:7月﹥8月﹥9月﹥5月﹥6月;月平均呼吸速率值区间在1.272～3.702μmol·m^-2 s^-1,平均值为2.323μmol·m^-2 s^-1。生长初期5月、中期7月和末期9月的单日呼吸速率变化均呈单峰曲线,峰值在12:00～16:00出现,最小值在03:00～06:00出现。(2)生长季林地土壤呼吸速率对土壤湿度的敏感性高于土壤温度,与土壤0～15 cm层湿度之间具有极显著的指数相关关系(P﹤0.01),与温度之间存在显著的线性关系(P﹤0.05)。土壤呼吸速率与土壤温度、湿度之间具有极显著的复合线性关系(P﹤0.01),线性模型对生长季土壤呼吸碳通量的预测具有参考意义。     

择伐对生长季针阔混交林土壤分室呼吸的影响

采用LI-8100土壤CO2排放通量全自动测量系统和与之配套的土壤温度、湿度传感器,对小兴安岭带岭林业局东方红林场观测样地不同强度择伐后,测定林地生长季土壤分室呼吸速率以及10 cm土深处的温度和湿度,探讨生长季土壤各分室呼吸的年际变化.结果表明:枯枝落叶层土壤呼吸速率生长季平均值呈逐年增加的趋势,观测期内枯枝落叶层土壤呼吸速率均值与采伐强度呈二次相关的关系(R2=0.806);根系呼吸速率生长季平均值逐年变化较复杂,差异较大,观测期内根系呼吸速率均值与采伐强度亦呈二次相关的关系(R2=0.415);矿质土壤呼吸速率生长季平均值呈逐年增加的趋势,与采伐强度相关性不显著.土壤温度和湿度是影响土壤分室呼吸速率变化的2个重要因素.枯枝落叶层和矿质土壤层是控制择伐后林地土壤呼吸变化的关键组分.为降低择伐后林地CO2排放增加速率,应选用中小强度(52%以下)的择伐作业.     

秦岭野生春兰光合特性研究

为了探索秦岭野生春兰[Cymbidium goeringii(Rchb.f.) Rchb.f.]的光合特性,从而为野生资源保护和春兰的栽培管理提供依据,本实验用Li-6400便携式光合分析仪对秦岭野生春兰的光合特性进行了研究。研究结果表明,春季春兰的净光合速率日变化曲线呈双峰型,最高峰出现在10:00,次高峰出现在14:00,在中午12:00出现光合"午休"现象;冬季净光合速率日变化曲线呈单峰型,最高峰出现在11:00。春兰冬季净光合速率总体小于春季。净光合速率与气孔导度和胞间二氧化碳浓度之间不存在统计意义上的相关性。气孔导度与温度存在极显著负相关(R=-0.911),与空气相对湿度存在极显著正相关(R=0.856)。空气相对湿度是影响春兰光合的一个重要因子。春兰的光补偿点为55μmol/m~2·s,光饱和点为620μmol/m~2·s。     

西宁市城市典型绿地空气负氧离子浓度特征研究

为了解西宁市城市森林不同功能区的空气负氧离子浓度及其与环境质量的关系,笔者选择了西宁市5个典型绿地进行了全天和全年空气负氧离子浓度及环境条件的测定。结果表明:1)5个城市典型绿地空气负氧离子浓度有显著差异(F=66.47,Sig0.05),平均值为400.1个/cm3.其中,植物园、省委家属院和麒麟湾高出世界卫生组织(WHO)规定的清新空气负氧离子最低浓度需达到250个/cm3的标准;海湖大道和新宁广场的空气负氧离子浓度低于标准。2)植物园、麒麟湾和省委家属院的空气负氧离子浓度日变化呈双峰曲线,9:00和17:00为峰顶,7:00,15:00和19:00为峰谷,其中9:00为最高峰段。海湖大道和新宁广场空气负氧离子浓度日变化平缓。3)植物园、麒麟湾和省委家属院空气负氧离子浓度的年变化呈单峰曲线,高峰出现在7月至9月份。新宁广场年变化平缓,海湖大道年变化复杂。4)5个绿地的空气负氧离子浓度与绿地类型、温度和相对湿度呈正相关,与风速、PM2.5和PM10.0呈负相关。空气负氧离子浓度与环境因素间的曲线拟合以一次方程的拟合优度最好。     

森林草原过渡区森林凋落物分解初期规律研究

为了探索内蒙古大兴安岭南段森林草原过渡区凋落物分解规律和调节生态系统物质循环和能量流动的载体作用,本文采用网袋法对杨桦次生林凋落物分解状况进行了研究,结果表明:经过非生长季的冻融破碎过程白桦和山杨林的凋落物失重率分别变为51.34%和38.71%,生长季的分解变化不大,总体与土壤温度和含水量显著相关;凋落物失重模式分别为:y白=0.312e-0.4721t(R2=0.9347);y山=0.035e-0.3502t(R2=0.9601)。凋落物N、P、K 3种养分元素及有机碳含量的迁移规律从前1年的秋季到第2年的秋季基本呈"释放—富集"模式,生长季刚开始时养分动态均呈下降趋势,开始富集的转折点基本在分解210~240 d左右,到分解360 d时富集最大。由此可知:凋落物分解、养分元素迁移过程可能不以微生物分解为主导,降雨淋溶、物理破碎等非生物因素可能作用显著。     

福州旗山常绿阔叶混交林空气含氧量日变化特征

运用PTM400氧气分析仪和气象测定仪对福州旗山森林公园中常绿阔叶混交林和停车场进行24小时连续同步观测,据此分析出2类观测点内空气含氧量的日动态变化规律以及常绿阔叶混交林中空气含氧量与气象因子之间的关系。结果显示:1)2类观测点内空气含氧量一天24小时的变化规律相似,呈抛物线形曲线变化,峰值都出现在下午15∶00,呈现出"昼高夜低"的变化规律;但在常绿阔叶混交林中,其各时段空气含氧量都比停车场高,且差异显著。2)常绿阔叶混交林空气氧气含量与空气温度呈极显著正相关,与光照强度呈显著相关,与空气湿度呈及显著负相关,与平均风速的相关性不显著。空气含氧量与气象因子的相关系数排序为空气温度空气湿度光照强度风速。     

1972—2005年大兴安岭林区雷击火特征及其与干旱指数的关系

对1972—2005年大兴安岭林区雷击火特征及其与Palmer干旱指数(PDSI)和Keetch-Byram干旱指数(KBDI)的关系分析表明:雷击火主要发生在5—9月,峰值出现在6月,约占全年雷击火次数的42%;雷击火的最大过火面积出现在5月和6月,约占全年过火总面积的85%。雷击火发生次数和面积的月动态均呈单峰型曲线变化,不同干旱指数的动态不同,其中KBDI的月动态呈单峰型曲线变化,5,6,7月最干旱;而PDSI则呈弱单峰型曲线变化,5月较干旱,6月和7月则较湿润。雷击火的年发生次数与9月的PDSI(R2=0.47,P<0.01)或6月和8月的KBDI(R2=0.57,P<0.01)关系密切,年过火总面积则与8月的PDSI(R2=0.20,P<0.01)或6月的KBDI(R2=0.40,P<0.01)有一定的关系。KBDI更适于描述大兴安岭林区的雷击火特征。     

武威绿洲日光温室葡萄主要病害发生规律及综合防治

调查总结了武威绿洲日光温室葡萄主要病害霜霉病、白粉病、白腐病的发生规律,并在实践的基础上提出了不同病害的防治适期和防治关键技术.     

A long-term study on the population dynamics of the grape leafhopper (<Emphasis Type="Italic">Empoasca vitis</Emphasis>) and antagonistic mymarid species

The population dynamics of the grape leafhopper (Empoasca vitis) and its egg parasitoids (Mymaridae) were studied at five representative sites in the Franconian wine-growing region from 1998 to 2001. In contrast to other German wine-growing areas, only one generation of grape leafhoppers per season was observed. In general, irrespective of the application of insecticides, the peak density of the first generation was much lower than that of immigrating grape leafhoppers. As the observed mymarid:leafhopper ratios (1:0.8–1:4.8) of the first generation were extremely high, egg parasitoids might be effectively controlling the grape leafhopper in Franconian vineyards. Slightly elevated leafhopper densities at the end of the growing season were caused by migrating sister species. Intervention thresholds were rarely reached; however, stress symptoms as discoloured intercostal leaf areas or rolled leaf edges were widespread. Over the whole study period three mymarid species occurred at all monitoring sites: Anagrus atomus, Stethynium triclavatum and a species, not previously reported in the German wine-growing region, Anagrus avalae. The dominance relationships of these species were site-specific, differing more strongly between than within sites; however, differences could not be related to the kind of management or natural surrounding of the vineyards. A hatching experiment confirmed the biological significance of A. avalae as an effective antagonist.     

Seed dispersal phenology and dispersal syndromes in a subtropical broad-leaved forest of China

This study describes the dispersal phenology and syndromes in Gutianshan 24 ha plot in a subtropical broad-leaved forest of China. The 130 0.5 m² seed traps collected 69,115 mature seeds, representing 27 species (belonging to 24 genera, and 15 families) in 12 months. One marked peak in the number of seeds and species during the year was found in dry season (November). Zoochory was the most common dispersal syndrome (70.4%), followed by anemochory (18.5%), ballistic dispersal (11.1%). Among fruit types, berry (33%), capsule (22%), nut (18%), and drupe (11%) were common in the subtropical evergreen forest. In fruit color, brown was the commonest (40%), followed by dark brown (30%), black (15%), red (11%), and yellow (4%). Overall, the community level seed rain study revealed that one marked peak in seed number occurred in the middle of dry season; zoochory was the principal dispersal mode of woody plants in subtropical forest, and dry seasons favor seed dispersal by animal and wind.     

Consequences of dry-season seed dispersal on seedling establishment of dry forest trees: Should we store seeds until the rains?

We examined the following hypotheses: (i) seeds of dry forest trees have high pre- and post-germination mortality by desiccation due to the time between seed dispersal and germination and to irregular rains at the onset of the rainy season; (ii) seedlings from seeds dispersed in the dry season which survive the dry spells are larger at the end of the first rainy season than those dispersed in the rainy season because the former have more time to grow. We evaluated the possible trade-off between few large seedlings (resulting from natural dispersal) × many small seedlings (resulting from delayed dispersal) on seedling survival during the dry season. We sowed eight tree species in a greenhouse in September, simulating the natural dispersal timing (before the rains), and in November, when rains are more constant. Because shading can counteract the effects of desiccation, we applied three levels of shade (10%, 40% and 72% of PPFD). From September 2005 to December 2006, we provided the daily precipitation of a median year from a major patch of dry forest in Central Brazil. At the end of the rainy season, a subset of seedlings was collected for growth measurements (dry mass) and the remainder was left to follow the dry season survivorship. The lower germination expected for seeds dispersed in the dry season and in full sun was not confirmed for species that had some dormancy. The delayed dispersal was advantageous for the initial establishment of fast germinating species, but it was irrelevant or even disadvantageous for others. Also, the greenhouse weather was certainly milder than the natural environment, reducing the potential for mortality by desiccation. The growth of the four species of higher dormancy were not affected by timing of seed dispersal, while three out of four fast germinating species had higher root biomass when dispersed in the dry season. The growth during the rainy season did not affect seedling survival during the dry season. Keeping seeds to sow when rain is constant might be a good strategy to increase the establishment of fast-germinating tree species.     

几丁聚糖控制月季霜霉病的研究

几丁聚糖是几丁质脱乙酰基后得到的一种氨基多糖。其产品0.5%OS-施特灵可控制月季霜霉病Peronospora sparsa，每隔10天以500倍液连续施药3次，控制效果达80％左右。     

黄土区人工林的土壤持水力与有效水状况

以晋西北黄土区河北杨林,小叶杨林和柠条灌木林为对象,就各人工林地的土壤持水力和在４个不同降水的土壤有效水动态特点进行了研究。结果表明,林地间土壤持水力和比水容量为：河北杨林〉小叶杨林〉柠条灌木林。各林地的土壤持水力和供水力普遍偏低。     

葡萄浆果中的糖成分以及相关代谢研究的进展

葡萄中的糖种类与含量对浆果品质及葡萄酒的质量具有重要影响,因此关于葡萄果实糖分的研究就显得尤为重要.该文就果实中糖分的生理功能、糖分对葡萄浆果品质及葡萄酒质量的影响以及蔗糖代谢相关酶在果实糖分积累中的作用等方面进行了研究,以期为这一领域的深入研究提供一定的理论依据.     

肉桂人工林土壤速效养分与酶活性的季节变化

研究了广西高峰林场林龄为3年和6年的肉桂人工林土壤速效养分(水解N、速效P、速效K)和土壤酶活性(过氧化氢酶、脲酶、酸性磷酸酶)的季节变化规律及其相互关系。结果表明：两种林地土壤速效养分含量和土壤酶话性均表现出明显的季节动态．：E壤速效N、P、K含量和L壤脲酶活性均以肉桂生长初期(3月中旬)最高．其次是第一个生长高峰期(6月中旬)或第二个生长高峰期(9月中旬)，最低是生长未期(12月中旬)；而土壤过氧化氢酶和酸性磷酸酶活性以第一个生长高峰期或第二个生长高峰期最高．其次是生长初期,最低是生长末期；士壤速效养分与土壤酶活性的季节变化密切相关。因此，生长初期至第一个生长高峰期是肉桂林地施用N、P、K肥的适当时期。     

Height growth of young larch (Larix kaempferi) in relation to the frequency of deer browsing damage in Hokkaido, Japan

The effect of browsing frequency by Sika deer (Cervus nippon yezoensis) on the height growth of Japanese larch (Larix kaempferi) in Hokkaido, Japan, was analyzed. Tree heights at the time of the census and at the start of the current growing season were determined for 100 trees selected randomly at each site. The tallest shoot on each tree was identified and the number of browsing occurrences on the current-year shoot was determined. Young larches browsed by deer repeatedly develop new shoots during a growing season. Larch is a browsing-tolerant species, and the average height growth of the most heavily browsed trees was >15 cm. Although resprouting partly compensated for decreased height growth caused by browsing, the annual increase in height decreased with increased browsing frequency. Thus, browsing frequency during a growing season best reflects the intensity of browsing damage to larch trees.     

Height development of Betula pubescens following precommercial thinning by breaking or cutting the treetops in different seasons

Topping, i.e. cutting or breaking the treetops of secondary stems, may be an attractive alternative to traditional precommercial thinning. The survival and height development of downy birch (Betula pubescens Ehrh.) after topping were examined over three growing seasons in two dense, naturally regenerated stands, 3.1–3.5 m high, in northern Sweden. The topping was performed in experiments with a two-factor randomized complete block design, as follows. Three treatments were applied to individual secondary stems (top-breaking at half the sample tree mean height, top-cutting at half the sample tree mean height, and traditional cutting just above ground) at each of three times: winter, spring and summer (in frozen, dormant and growing conditions, respectively). A control (no treatment) was also included. The survival rate was lowest for traditionally cut stems and for stems cut in growing conditions. Height development after three growing seasons was significantly affected by time of treatment, the height growth being lowest after treatment in growing conditions, but not by treatment. Height growth of control stems was not significantly different from height growth in any combination of treatment and time of treatment, after three growing seasons. However, control stems had the greatest leading shoot length in the third growing season.