A review of Turkish saproxylic beetles from the European Red List

The conservation of beetles that depend on dying or dead wood (i.e. saproxylic), has received a great deal of attention in many parts of the world in recent years. Human activities such as urbanization and logging, and their results, e.g. global warming, destroy natural ecosystems and threaten unusual species such as Lucanus cervus (L. 1758), Rosalia alpina (L. 1758), Limoniscus violaceus (Müller 1821) and Osmoderma eremita (Scopoli 1763). Attempts have been made to conserve the habitats upon which these species depend. Although represented by a large number of species, saproxylic beetles in Turkey have not received much attention. Although some Turkish studies have acknowledged their value, comprehensive investigations of these species are very limited. The aim of this study is to make a list, from the literature, of the species that are endangered in Europe and found in Turkey, to highlight the importance of these species. The research includes 151 saproxylic beetle species belonging to the families Bostrichidae, Cerambycidae, Elateridae, Eucnemidae, Scarabaeidae, Euchiridae, Lucanidae and Mycetophagidae. The list of Turkish saproxylic beetles was prepared using the European Red List of Saproxylic Beetles. Information is provided about the IUCN Red List category in Europe, the locations of the species in Turkey, and their global geographic range. We gathered all data about these species from the international literature. Furthermore, we also include in the list certain species whose locations are not specified, but which inhabit Turkey. We obtained their records from some catalogs in Turkey. In addition to the list, we prepared three distribution maps for Turkey. The maps show distribution in Turkey of some species in the Endangered, Vulnerable and Near Threatened categories in the European Red List. It is expected that this study will lead to comprehensive studies on saproxylic beetles from Turkey.     

Genotypic difference in salinity tolerance in quinoa is determined by differential control of xylem Na loading and stomatal density

Quinoa is regarded as a highly salt tolerant halophyte crop, of great potential for cultivation on saline areas around the world. Fourteen quinoa genotypes of different geographical origin, differing in salinity tolerance, were grown under greenhouse conditions. Salinity treatment started on 10 day old seedlings. Six weeks after the treatment commenced, leaf sap Na and K content and osmolality, stomatal density, chlorophyll fluorescence characteristics, and xylem sap Na and K composition were measured. Responses to salinity differed greatly among the varieties. All cultivars had substantially increased K⁺ concentrations in the leaf sap, but the most tolerant cultivars had lower xylem Na⁺ content at the time of sampling. Most tolerant cultivars had lowest leaf sap osmolality. All varieties reduced stomata density when grown under saline conditions. All varieties clustered into two groups (includers and excluders) depending on their strategy of handling Na⁺ under saline conditions. Under control (non-saline) conditions, a strong positive correlation was observed between salinity tolerance and plants ability to accumulate Na⁺ in the shoot. Increased leaf sap K⁺, controlled Na⁺ loading to the xylem, and reduced stomata density are important physiological traits contributing to genotypic differences in salinity tolerance in quinoa, a halophyte species from Chenopodium family.     

干旱荒漠区银白杨树干液流动态

应用热扩散式树干茎流计(TDP)于2012年7月1日至7月25日,在克拉玛依地区农业开发区对银白杨(Populus alba L.×P.talassica)人工林树干液流速率进行了连续测定,并对气象、土壤水分等指标进行了同步测定。结果表明:7月份的晴天银白杨树干液流速率日变化呈单峰型,阴天呈多峰型,在测量时期液流速率日平均值为0.6059 L/h;银白杨树干单位边材面积的液流速率与太阳总辐射、大气温度、水汽压差呈极显著正相关关系,与相对湿度呈负相关关系。其相关系数绝对值顺序为太阳总辐射>大气温度>水汽压差>相对湿度>风速;银白杨边材面积与胸径之间存在着显著的线性相关关系,相关系数为0.834,单位边材面积的液流速率随树干胸径的增大而减小。     

内蒙古武川县农田退耕还草对粪金龟子群落的影响

2006年5-9月,诱捕法采集粪金龟子,以农田为对照,选择内蒙古武川县不同农田退耕管理方式为研究样地,分析了农田退耕后采取不同管理方式对粪金龟子群落的影响,以为农田退耕还草管理措施生态效应的评价和完善提供依据.共捕获粪金龟子21671头,隶属于3科5属25种.优势种为直蜉金龟(Aphodius rectus)和蜉金龟属(Aphodius sp.7),占总捕获量的比例分别为59.34％和11.71％.几种退耕管理方式都导致粪金龟子群落物种丰富度、生物量和多度提高,且具有显著的季节特征.Pearson相关分析表明,粪金龟子群落的物种丰富度、生物量和种数以及不同功能群和主要种的个体数与退耕年限、平均草高和植物群落盖度的变化存在显著正相关关系(P＜0.01或P＜0.05).由于长期农业耕作以及缺少大型食草动物和较大面积放牧草地,研究地区的粪金龟子群落组成以功能群Ⅱ和Ⅲ为主,功能群Ⅰ的多度和物种丰度较低.可以认为,在研究地区以农田景观为主要基质的区域,采取多样化的农田退耕管理方式,提高了生境的空间异质性,在减少人为耕作活动对粪金龟子影响的基础上,对粪金龟子物种丰度和多度的维持起到了促进作用.农田退耕、保留适当面积放牧草地或适当数量大型放牧家畜将有利于功能群Ⅰ物种丰度和多度的提高,有益于粪金龟子群落物种多样性和整体生态功能的维持.     

模拟酸雨对蒙古栎幼苗生长和根系伤流量的影响

选择中国北方落叶阔叶林的主要组成树种蒙古栎(Quercus mongolica Fisch.ex Ledeb.)的1年生幼苗为研究对象,设置4个酸雨酸度(重度、中度、轻度和对照)和3个降雨量(自然雨量和增、减雨量30％),以期阐明酸雨对蒙古栎幼苗形态生长、生物量和根系伤流量的影响,探讨中国北方日趋严重的酸雨是否会影响蒙古栎幼苗的生长,为酸雨区森林恢复植物的选择提供依据.研究结果显示:1)在本实验的酸雨酸度下,酸雨降雨量的增加对蒙古栎幼苗各生理生态指标均有一定的促进作用;2)酸雨酸度对蒙古栎幼苗形态和生物量的影响不显著,但酸度增加降低了幼苗的根系伤流量;3)增雨的重度酸雨处理促进了蒙古栎幼苗形态生长和生物量累积;4)两因素对蒙古栎幼苗的影响没有交互作用.说明蒙古栎对酸雨具有一定的抗性,可考虑选择为酸雨区植被构建的物种.     

光照强度对大花旋蒴苣苔叶形态和生理指标的影响

以复苏植物大花旋蒴苣苔(Boea clarkeana)为盆栽实验材料,通过梯度遮光处理,研究不同光照强度(100%、80%、60%、40%和20%透光率)和不同处理时间(30、60、90、120和150d)对大花旋蒴苣苔叶生长指标和生理指标的影响。结果表明:随着光照强度的减弱,大花旋蒴苣苔叶的各生长指标(叶片长、叶片宽、叶柄长、叶柄直径以及叶面积)呈现先增大后减小的趋势,透光率为60%时达到最大值;全光照(100%透光率)时,大花旋蒴苣苔表现出明显的外伤症状,透光率为80%和20%时,分别表现出中度伤害和轻度伤害,透光率为40%和60%时,未出现明显的外伤症状;过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和过氧化物酶(POD)3种抗氧化酶活性均较低且随着光强减弱呈现先降低后升高的趋势,随着处理时间的延长呈先上升后下降的趋势,全光照时抗氧化酶的活性最大,透光率60%处理下酶活性相对较低;丙二醛(MDA)含量、脯氨酸(Pro)含量和质膜透性随着光强减弱呈先降低后升高的趋势,随着处理时间的延长显著升高;叶绿素含量随着光强减弱呈逐渐上升的趋势,随着处理时间的延长先降低后升高。分析表明,40%～60%的透光率有利于大花旋蒴苣苔的生长,强光和弱光对大花旋蒴苣苔的生长均不利。     

Impact of elevated CO2 and increased temperature on Japanese beetle herbivory

To examine how the major elements of global change affect herbivory in agroecosystems, a multifactorial experiment was conducted where soybeans were grown at two levels of carbon dioxide and temperature, including those predicted for 2050, under otherwise normal field conditions. Japanese beetles (Popillia japonica Newman) were enclosed on foliage for 24 h, after which the beetle survivorship, total and per capita leaf consumption, and leaf protease inhibitor activity were measured. The direct effect of temperature on beetle consumption and survivorship also was measured under controlled environmental conditions. No differences in total foliage consumption were observed; however, beetles forced to feed at elevated temperature in the field demonstrated greater per capita consumption and reduced survivorship compared to beetles feeding at ambient temperature. Survivorship was also greater for beetles that consumed foliage grown under elevated CO₂, but there were no interactive effects of CO₂ and temperature, and no differences in leaf chemistry were resolved. Leaf consumption by beetles increased strongly with increasing temperature up to ～37° C, above which increased mortality caused a precipitous decrease in consumption. An empirical model based on the temperature dependence of leaf consumption and flight suggests that the 3.5°C increase in temperature predicted for 2050 will increase the optimal feeding window for the Japanese beetle by 290%. Elevated temperature and CO₂ operating independently have the potential to greatly increase foliage damage to soybean by chewing insects, such as Popillia japonica, potentially affecting crop yields.     

The relationship between the amount of insect-repelling phenolic compounds in pennywort tea and the number of infesting cigarette beetles in the tea bag during one-year storage

Cigarette beetle, Lasioderma serricorne (F.), is a common food-product pest widely found in homes. This paper investigated the relationship between the number of infesting cigarette beetles and the phenolic content of pennywort tea made from young and mature leaves during one-year storage. It was found that cigarette beetles started to appear in tea bags after six months of storage. More adults were found than larvae and pupae. In addition, the number of cigarette beetles infesting pennywort tea made from mature leaves was higher than when it was made from young leaves. The amount of phenolic compounds in pennywort tea was analyzed by Folin–Ciocalteau assay. The results of a regression analysis indicated that the number of adult cigarette beetles correlated negatively with the amount of phenolic compounds in pennywort tea made from young leaves – when the total phenolic content decreased, the number of infesting cigarette beetles increased (r² = 0.80). The number of larvae and pupae showed a weak negative correlation with the amount of phenolic compounds (r² = 0.40 and r² = 0.56, respectively). Similar correlations were found in pennywort tea made from mature leaves, but the number of infesting beetles was higher due to the lower phenolic content of the mature leaves.     

Stomatal acclimation to vapour pressure deficit doubles transpiration of small tree seedlings with warming

Future climate change is expected to increase temperature (T) and atmospheric vapour pressure deficit (VPD) in many regions, but the effect of persistent warming on plant stomatal behaviour is highly uncertain. We investigated the effect of experimental warming of 1.9–5.1 °C and increased VPD of 0.5–1.3 kPa on transpiration and stomatal conductance (g_s) of tree seedlings in the temperate forest understory (Duke Forest, North Carolina, USA). We observed peaked responses of transpiration to VPD in all seedlings, and the optimum VPD for transpiration (D_opt) shifted proportionally with increasing chamber VPD. Warming increased mean water use of Carya by 140% and Quercus by 150%, but had no significant effect on water use of Acer. Increased water use of ring‐porous species was attributed to (1) higher air T and (2) stomatal acclimation to VPD resulting in higher g_s and more sensitive stomata, and thereby less efficient water use. Stomatal acclimation maintained homeostasis of leaf T and carbon gain despite increased VPD, revealing that short‐term stomatal responses to VPD may not be representative of long‐term exposure. Acclimation responses differ from expectations of decreasing g_s with increasing VPD and may necessitate revision of current models based on this assumption.