为探索松墨天牛取食对林木的分解作用,本文通过对松墨天牛幼虫及成虫取食量的测定,寄主云南松韧皮组织及松墨天牛幼虫排泄物成分对比分析,并与资源利用相同的木材微生物分解能力进行对比,阐明了松墨天牛作为分解者的重要分解作用。研究表明,松墨天牛幼虫期(约为55 d)取食分解林木生物量平均为12.42 g(24.40 cm3),成虫期取食分解林木生物量平均为12.87 g(25.28 cm3);松墨天牛幼虫对糖类物质的利用度很高,具有较强的纤维分解利用能力,取食分解后总糖减少83.58%,粗纤维减少23.87%,1头松墨天牛幼虫期分解的林木粗纤维质量为1.93 g,分解利用率为0.008 g·d-1。松墨天牛对林木的分解证明,天牛作为一种重要的林木分解的先驱者,可以分解林木,更重要的是松墨天牛攻击亚健康林木,为微生物分解林木提供了容易入侵的途径,加速了亚健康林木的分解与循环,在森林生态系统物质分解与循环中具有重要的促进作用。

研究了松墨天牛幼虫、纵坑切梢小蠹幼虫和成虫消化酶的主要种类和活性。分析结果表明, 松墨天牛幼虫有10种消化酶, 纵坑切梢小蠹幼虫和成虫有8种消化酶。松墨天牛幼虫的消化酶活性大小排列顺序为: 果胶酶> 淀粉酶> Cx酶> 半纤维素酶> 转化酶> β-1, 4??葡萄糖苷酶> C1酶> 脂肪酶> 类胰蛋白酶> 胃蛋白酶; 小蠹幼虫和成虫不含Cx酶和β-11, 4??葡萄糖苷酶, 活性顺序均为: 果胶酶> 淀粉酶> 半纤维素酶> 转化酶> C1酶> 类胰蛋白酶>脂肪酶> 胃蛋白酶。在55 ℃ 、pH 值8. 6时, 果胶酶活性最高。

The vertical distribution characteristics of Monochamus alternatus on the trucks of infested Pinus yunnanensis were investigated both in field and laboratory. The results showed that the quantity distribution of oviposition scar in trunk was lower part > middle part > upper part; and the density distribution of oviposition scar had not significant difference (P>0.05). The quantity distribution of entrance hole in trunk was middle part > lower part > upper part; and the density distribution of entrance hole was upper part > middle part > lower part. The quantity distribution of exit hole in trunk was middle part > upper part > lower part; and the density distribution of exit hole was upper part > middle part > lower part. There were positive correlations between the quantities of oviposition scar or entrance hole in lower part of trunk and the entrance hole or exit hole in whole trunk, respectively. The linear regression equations of the quantity of oviposition scar in lower part (x1), the entrance hole in lower part (x2) and the quantity of oviposition scar in whole trunk (y1), the entrance hole in whole trunk (y2), the exit hole in whole trunk (y3) are y1=7.117+2.283 x1,y2=24.220+0.701 x1,y3=8.794+0.434 x1,y2=28.805+2.211 x2,y3=20.367+0.778 x2. All partial correlations had reached the very signiticant level.

通过对云南省滇中地区云南松天然林和人工林的群落结构调查及物种多样性研究,结果表明:干扰较少的云南松天然林具有较为稳定、合理的群落结构,其乔木层优势种群具有较强的自然更新能力和长远的演替潜力,并且物种多样性和生境多样性。干扰较少的云南松天然林的这些特性均优于干扰较大的云南松天然林,干扰较大的云南松天然林又优于人工林。随着森林起源过程中干扰(人为干扰和自然干扰)程度的逐渐增加,云南松群落的稳定性、生物多样性、协调平衡能力及自然修复能力相应下降;而入侵种紫茎泽兰的分布范围和数量则相应上升,提示其或可作为森林群落生物多样性、干扰程度和森林健康评价的指示生物。

广泛收集云南松地理分布资料,应用地理信息系统ArcGIS,制作云南松物种的分布现状图,并根据Climate China预测模型确定云南松分布区间的气候参数,利用Kira的温暖指数(WI)、寒冷指数(CI)、干燥度指数(K)、徐文铎湿度指数(HI)、holdridge生物温度(BT)、可能蒸散量(PET)、可能蒸散率(PER)以及单一气候因子如年平均气温(MAT)、1月平均气温(TAV01)、7月平均气温(TAV07)、年降水量(MAP)、>5 ℃积温(DD5)、>18 ℃积温(DD18)、极端最高气温(MWMT)、极端最低气温(MCMT)、气温年较差(TD)、年热湿比(AHM)等指标,研究云南松的地理分布与气候关系,讨论了云南松垂直分布上下限以及北界的热量状况。主成分分析结果表明:影响云南松地理分布的主要因素依次为:温度、湿度、气温年较差。

The pine shoot beetle Tomicus yunnanensis (Kirkendall and Faccoli) (Coleoptera: Curculionidae: Scolytinae) is one of the main pests of pine forest in southwest China. Its life cycle involves reproduction in the phloem of trucks or larger brunches of dead or weakened trees, followed by a long maturation feeding by callow adult in shoots of healthy trees which often cause massive tree death. A simple and practical method for rearing T. yunnanensis was set up using host timber segments and artificial pupal cells by continuous rearing works within past four years. Then its experimental population was established in laboratory and the living habits during the latent phase were observed using this new rearing method. The results show that it completes three generations in one year under laboratory condition in Kunming, Yunnan Province. The mean time of each generation is 101 days, and the mean survival rate is 92.4%. A mating female begins to oviposit after 6 days and may last 122 days. The average oviposition number is 429 per female in its life time. The method is easy to operate and may provide effective approaches for getting standard experimental insects for further research.

基于云南省气象数据与云南松空间分布数据,结合国际上应用较广的Kira指标,通过统计方法和GIS软件,分析了云南省气候资源时空变化特征以及云南松未来适生区域的变化。结果表明:云南松的温暖指数为32.1 204.3 ℃·月,最适范围为86.1 160.0 ℃·月,平均值122.9 ℃·月;云南省WI年际变化曲线呈明显升高,从1970年的121.30 ℃·月升至2002年的133.57 ℃·月;HI年际变化曲线呈下降趋势,从1970年的10.97 mm·(℃·月)-1降至2002年的8.92 mm·(℃·月)-1,WI波动较HI显著,最高值出现在1998年,为136.63 ℃·月,最低值为1976年的117.13 ℃·月,但均在云南松最适分布范围内。基于Kira温暖指数预测:未来气候变化下,云南松分布仍集中于滇中地区,但分布面积发生了较大变化,云南松分布北界移动不明显,但云南松总体适生面积将逐步减少。