杨树人工林冻害综合防治技术的研究

杨树人工林冻害综合防治技术的研究赵经周，杨运启，黄居平，张铁军（黑龙江省森保所）（黑龙江省苇河林业局）朱传富，杨文学，聂凤林，于建君（苇河林业局青山种子园）（苇河林业局气象站）杨树冻害发生的主要原因，一方面取决于杨树本身的耐冻性，另一方面取决于生态环...     

杨树人工林林木蓄积量调查方法对比研究

采用全林每木检尺法、标准地调查法、样圆调查法、角规调查法对同一块杨树人工林林木蓄积量进行调查,比较了不同调查方法的调查精度与工作量大小.结果表明：四种调查方法调查所得林木蓄积量无明显差异.以全林每木检尺法调查的林木蓄积量为标准值,标准地调查法所测数据精度最高,其次为样圆调查法、角规调查法.从调查工作量上来看,全林每木检尺法工作量最大,样圆调查法与角规调查法操作容易,工作效率较高.     

不同治理模式下沙质草原区风蚀破口植被恢复效果研究

选取浑善达克沙地南缘沙质草原风蚀破口不同植被恢复模式,对人工林和林下草本层、土壤进行调查,研究了采取不同治理措施9年后的恢复效果。结果表明：在7种不同治理措施下,造林树种生长状况良好,保存率均达到85%以上;在不同模式下,林下草本层发育和生长受到明显影响。樟子松＋山杏混交林、柠条锦鸡儿纯林模式下,林下草本植物丰富度和盖度较高。黄柳＋杨柴＋小叶锦鸡儿混交林下草本种类少,盖度和地上生物量较低。杨树＋沙棘混交林、柠条锦鸡儿纯林草本群落中赖草、冰草占优势。沙棘和杨柴林下草本层以沙蓬、黄蒿、雾冰藜等1、2年生沙生植物为主;杨树＋沙棘混交林和沙棘纯林林下枯落物较多,其次为黄柳＋杨柴＋小叶锦鸡儿混交林和杨柴人工林,其他模式下还没有积累枯落物;樟子松＋山杏、杨树＋沙棘混交林、樟子松林0～40 cm土壤含水率维持在4%～8%之间。黄柳＋杨柴＋小叶锦鸡儿混交林、柠条锦鸡儿和沙棘人工林下土壤含水率均低于3%,而且在不同土层之间差异较小。     

不同材料对葡萄防寒效果的研究

对不同葡萄防寒材料（蓝膜＋30cm玉米秸、黑膜＋30cm玉米秸、黑膜＋20cm玉米秸、棉被、无纺布、单黑膜）的防寒效果与埋土防寒效果进行测定比较,并对不同材料的性价比进行评价。结果表明：棉被和黑膜＋30cm玉米秸处理的土壤温度较高,防寒效果最好,且春季的发芽率、成枝率、果枝率均明显优于其他几个处理。通过价格比较,使用棉被、黑膜＋30cm厚玉米秸作为防寒材料成本较低。棉被、黑膜＋30cm玉米秸均可作为葡萄的防寒材料。     

沐川天然林与人工水杉林保水功能比较

通过对四川沐川县天然林、人工林（水杉林）枯落物蓄积量调查分析和持水特性的研究结果表明：枯落物蓄积量为天然林＞人工林（25.7 t·hm-2＞ 18.1 t·hm-2）,最大持水量为天然林＞人工林（75.0 t·hm-2 ＞47.0 t·hm-2）,最大持水率为天然林＞人工林,各时段吸水量、吸水速率表现为天然林＞人工林,有效拦蓄量表现为天然林＞人工林（28.6 t·hm-2＞ 17.0 t·hm-2）.总体分析可以看出,天然林落物层保水功能相对要比人工林好.     

连栽杨树人工林碳储量变化

为研究连栽杨树人工林林木和土壤碳储量变化规律,了解杨树人工林碳汇能力,笔者对江汉平原1代和2代杨树人工林的林木生物量和碳储量、土壤碳含量和碳储量进行了测定,结果表明：1代和2代杨树人工林林木碳储量分别为30.83 t/hm2和24.63 t/hm2;土壤碳储量（0～20 cm）分别为39.29 t/hm2和29.09 ...     

林业信息

松、杉苗床用木屑覆盖好松、杉苗床以往都用稻草覆盖,鸟害较严重,若揭草不及时,常引起苗木黄化或弯曲,揭草后幼苗因环境突变而影响生长.浙江东阳县南江林场1984年育马尾松、杉木苗,用锯木屑覆盖(厚1—2毫米),种子场围发芽率高,幼苗出土整齐,生长健壮.同时,鸟害少,防止土壤板结,减少病害,增加土壤有机质,并可节省劳力.摘自《浙江林业科技》1985年第1期选用黑色地膜覆盖杨树插条育苗沈阳市林科所用聚乙烯(LDPE)吹塑黑、白、绿地膜进行杨树插条育苗试验.根据地膜含炭素的比例不同,设黑1、黑2、黑3、绿色、白色和未覆盖地膜(对照)六种处理.两年结果表明,选用黑色地膜优于其他颜色地膜和对照,尤以黑1地膜效果最好.     

不同药剂防治杨树食叶害虫的试验

利用不同配比度的3种喷雾剂（森得保可湿性粉剂、18％阿维菌素、25％灭幼脲3号）和2种烟剂（氯氰菊酯、敌敌畏）对杨树食叶害虫进行防治试验,结果表明常用的防治杨树食叶害虫这几种药剂均能起到很好的防治效果,7d的致死率均85％以上;致死中浓度（LC）测定分析结果显示,森得保可湿性粉剂与灭幼脲、敌敌畏＋柴油、氯氰菊酯＋柴油的LC50、LC90均存在显著差异,阿维菌与敌敌畏＋柴油、氯氰菊酯＋柴油尽在LC50上存在差异,其他各组别药剂对比差异均不显著。     

散射辐射比例对华北平原杨树人工林生态系统能量分配的影响

【目的】在全球辐射总量及其组成显著变化的背景下,明确散射辐射比例（Fdif）对华北平原杨树人工林生态系统能量分配的影响,为准确评估杨树人工林的生态服务功能和进一步完善生态系统过程模型提供科学依据。【方法】利用涡度相关技术和小气候观测,对2019、2021年生长季（DOY 91～304）杨树人工林生态系统的能量通量和环境因子开展研究。【结果】华北平原杨树人工林生态系统能量分配在生长季中期（DOY 152～243）以潜热通量（LE）为主,在生长季初期（DOY 91～151）和末期（DOY 244～304）以显热通量（H）为主。Fdif与波文比（β）呈显著负相关（P<0.01）,与冠层导度（Gs;P<0.01)、冠层分离指数（Ω;P<0.05)和Priestley-Taylor系数（α;P <0.01）呈显著正相关。通径分析结果表明,Gs是调节华北平原杨树人工林生态系统能量分配的主要因子,Fdif下降时,Gs降低,饱和水汽压差（VPD）增大,生态系统的β显著增大,进而改变生态系统能量分配模式。【结论】Fdif变化影响华北平原杨树人工林生态系统能量分配,Fdif下降会导...     

四川洪雅县3种植被模式的土壤入渗性能研究

土壤入渗性能是评价土壤水源涵养功能的重要指标。以四川洪雅县退耕还林还草工程中实施的3种植被模式（模式Ⅱ苦竹＋牛鞭草，模式Ⅲ撑绿杂交竹＋牛鞭草，农耕地作为对照）为研究对象，采用渗透筒法对其土壤入渗性能进行定位研究。据实测数据初步得出模式Ⅱ、模式Ⅲ及对照土壤入渗率与入渗时间之间存在对数函数关系。在此基础上，探讨三种植被模式土壤入渗率随季节变化的规律。研究表明：苦竹＋牛鞭草（模式Ⅱ）对土壤入渗性能的改良作用较大，农耕地居中．撑绿杂交竹＋牛鞭草（模式Ⅲ）的改良作用直到目前还不明显。     

黄土地区防护林生态系统土壤水分条件的分析与评价

从土壤水分变化特征、土壤水分有效性、影响土壤水分的林分因子综合分析等几个方面对黄土地区防护林生态系统土壤水分条件进行了分析与评价。研究表明，黄土地区防护林生态系统土壤水分的垂直变化可分为：土壤水分弱利用层、土壤水分利用层、土壤水分调节层三个作用层次；林地土壤水分的季节变化可分为：土壤水分消耗期、补偿积累期、消退期、稳定期四个时期；根据土壤水分对植物的有效性，将土壤水分划分成易效水、中效水和难效水三种状态。在时间和深度上，阴坡土壤的有效性要好于阳坡，乔木地土壤难效水出现的机率明显高于灌木林地和荒地。通过对影响土壤水分的林分因子的综合分析，得到刺槐和油松林地含水量和难效水的机率与林分因子之间的多元回归方程。     

金沙江干热河谷造林措施对土壤水分的影响

本文研究了干热河谷植被恢复中的造林措施对土壤水分水分的影响。以试验数据为基础,科学分析了挡水墙、覆膜、覆革和保水剂四种造林措施的优缺点,结果表明:(1)使用保水剂极为显著的提高了土壤水分含量;(2)挡水墙改善土壤水分能力较弱;(3)覆膜改变了土壤水分的分布格局;(4)覆革增加了水分下渗,改善了苗木根部的土壤水分。综合分析,保水剂和覆草能有效提高造林苗木土壤水分含量,具有极大的实用价值     

蕉岭长潭省级自然保护区不同林分类型土壤水分物理性质研究

对广东省蕉岭长潭自然保护区的阔叶混交林、马尾松林、杉木林、毛竹林、针阔混交林等五种典型林分的土壤水分物理性质进行了研究,结果表明：（1）五种林分类型土壤自然含水量、毛管持水量、最小持水量的排序为毛竹林〉针阔混交林〉马尾松林〉杉木林〉阔叶混交林;非毛管孔隙度和非毛管持水量的排序为针阔混交林〉阔叶混交林〉杉木林〉马尾松林〉毛竹林。（2）五种林分的非毛管孔隙度;阔叶混交林、杉木林、针阔混交林的总孔隙度;阔叶混交林的毛管持水量、最大持水量、最小持水量、非毛管持水量;针阔混交林的自然含水量、毛管持水量、最大持水量、最小持水量、非毛管持水量都是随着土层深度的增加而减少。阔叶混交林、毛竹林、杉木林、针阔混交林的土壤容重是随土层深度的增加而增加。（3）同一土层不同林分间的容重、孔隙度、自然含水量、最大持水量、毛管持水量、非毛管持水量和最小持水量都没有显著差异,而同一林分的物理性质和持水特性在不同土层之间存在显著差异。     

A new model to analyze water retention characteristics of forest soils based on soil pore radius distribution

The soil water retention model proposed by Kosugi was modified to have a relatively simple functional form. The resulting water retention model (the lognormal distribution model) contains two parameters which have physical significance on the water retention curve and are related directly to the statistics of the soil pore radius distribution functiong(r). The observed retention data sets of 282 undisturbed forest soils taken from Mashimo were analyzed using the lognormal distribution model, and it was shown that the model performs fairly well for every data set. The estimated parameters of the model indicated that the water retention characteristics of the undisturbed forest soils are related to the soil structure more closely than to the soil texture. Many crumb-structure forest soils have greater median ofg(r) than the crumb and granular-structure soils. Disturbed loamy soils have smaller median ofg(r) than many of the undisturbed forest soils and disturbed sandy soils have smallerg(r) width than the forest soils. The brown forest soils taken from A-horizon generally have the greater median ofg(r) than the brown forest soils taken from B-horizon. Some of the brown forest soils have the greater width ofg(r) than the black soils. The median ofg(r) of brown forest soil taken from A-horizon generally becomes greater as the soil moisture condition becomes wet.     

Pasture production and composition under poplar in a hill environment in New Zealand

Traditionally, poplar (Populus spp.) have been planted to control erosion on New Zealand’s hill-slopes because of their capacity to dry out and bind together the soil. Two systems: (1) widely spaced, planted poplar for soil conservation, and (2) non-eroded open pasture were compared to determine the relative effect of the poplar–pasture system on the production, nutritive value and species composition of the pasture, and on the water balance. Measurements were made at three sites with mature poplar (>29 years and 37–40 stems ha⁻¹) and at a replicated experiment with young poplar (5 years, 50–100 stems ha⁻¹). Soil water relations did not suggest strong competition for water between poplar and pasture. Pasture accumulation under mature poplar was 40% less than in the open pasture, but under young poplar was similar to that in the open pasture. Chemical composition of pasture suggested that feed quality of pasture in the open was better than under the poplar canopy, except during spring, when most chemical components were similar. At the most, in vitro digestibility of pasture dry matter was 8.9% lower and metabolisable energy of pasture dry matter was 1.5 MJ kg lower under the poplar canopy than in the open pasture. Shade tolerant species were not dominant in the plant community under the poplar canopy with grasses such as browntop (Agrostis capillaris, L.) and ryegrass (Lolium perenne, L.) being a high proportion of the plant community. Differences in chemical composition were related to differences in the botanical composition between the open pasture and the poplar understorey. It was concluded that the greatest effect of poplar was on pasture production due to shading, and that management of this silvopastoral system needs to focus on control of the tree canopy to lessen the decrease in pasture production.     

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。     

Process studies in aPinus radiata-pasture agroforestry system in a subhumid temperature environment. II. Analysis of dry matter yields in the third year

In this paper we analyzed the dry matter yields (DM) produced in an agroforestry trial consisting of pine trees grown over (1) Control (bare ground), (2) ryegrass/clovers (Lolium perene/Trifolium spp.), (3) ryegrass only, and (4) lucerne (Medicago sativa) during the third growing season between 1992 and 1993. In addition these pastures were grown alone in separate plots in the open. The results show that:

Effects of site preparation on soil properties and on morphology of Pinus sylvestris and Picea abies seedlings sown at different dates

The aims of the study are to find out the effects of site preparation on soil properties and on the morphology of three-year-old Pinus sylvestris L. and Picea abies (L.) Karst. seedlings sown at different dates along a slope with variation in soil texture, water, and fertility. Based on the hypothesis that soil texture affects soil water content, water retention capacity, and nutrient content, we studied site preparation of varying intensities: exposed C horizon, mounds (broken O/E/B horizons piled over undisturbed ground), and exposed E/B horizon. Though the growing time difference between sowings was about one month, after three growing seasons, spring-sown seedlings were larger than summer-sown seedlings. P. sylvestris seedlings were largest with mounds and smallest with exposed C horizon, but site preparation did not affect the morphology of P. abies seedlings.     

黄土高原寒区青海云杉人工林地土壤水分物理特性研究

对黄土高原高寒区的青海云杉人工林林地的土壤水分物理性质进行了实地观测和分析(主要采用野外实测土壤水分再分布的方法,对入渗后不同土层土壤的水分再分布过程及低吸力段土壤水分特征作了研究),发现该林地在枯落物及林下植被层的作用下,使得0~10 cm表层土壤的持水性最好;因放牧践踏导致林地10~30 cm土层的土壤板结密实,持水性较差;30~50 cm土层土壤的持水性居中。通过研究还拟合得出了该林地土壤水分再分布、土壤水分特征曲线及土壤比水容量的参数。为该地区退耕还林还草、林业生态建设和森林水文效益评价提供了可靠依据。     

岷江上游山地森林／干旱河谷交错带几种植被类型土壤含水量研究

采用烘干法和环刀法对土壤物理性质进行了测定,目的是为了重点了解岷江上游山地森林／干旱河谷交错带的不同植被类型下0～40cm土壤含水量的变化。经过2007年4月、7月、9月、11月四个不同时期的测定,结果表明：同一植被类型下（除灌木林地）土壤含水量9月份的最大,与当地的雨季呈现同增同减的关系,而灌木林地下的呈现从4月到1...