Warm Temperate Zone Research Articles

暖温带花岗岩风化壳中黑云母微量元素的富集与流失变化——以山东半岛院格庄花岗岩体风化壳为例

暖温带花岗岩风化壳中黑云母微量元素的富集与流失变化——以山东半岛院格庄花岗岩体风化壳为例

Detection model of soil salinization information in the Yellow River Delta based on feature space models with typical surface parameters derived from Landsat8 OLI image

The Yellow River Delta, with the most typical new wetland system in warm temperate zone of China, is suffering from increasingly serious salinization. The purpose of this study is to utilize five typical surface parameters, including Albedo (the surface Albedo), NDVI (vegetation index), SI (salinity index),WI (humidity index), and (Iron oxide index), to construct 10 different feature spaces and, then, propose two different kinds of monitoring models (point-to-point model and point to line model) of soil salinization. The results showed that the inversion accuracy of the feature space detection index based on the point-to-point model was the highest with R 2=0.86. However, the inversion accuracy of Albedo-NDVI feature space detection index based on the point-to-point model is the lowest with R 2=0.72. This is due to the fact that NDVI is not sensitive enough to indicate the status of vegetation grown in the region with low (disturbance of soil background) and high (influenced by the saturation effect) vegetation coverage. The chemical weathering is also a primary cause of soil salinization, during which Fe2O3 is formed by the reaction of oxygen present in the atmosphere with primary Fe2+ minerals in the soil .Therefore, the feature space detection index based on the point-to-point model has a stronger applicability to monitor the information of soil salinization in the Yellow River Delta. This above point-to-point detection model can be utilized as a better approach to provide data and decision support for the development of agriculture, construction of reservoirs, and protection of natural ecological system in the Yellow River Delta.

模拟穿透雨减少对锐齿栎(Quercus aliena var. acuteserrata)树干液流密度的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 模拟穿透雨减少对锐齿栎(Quercus aliena var. acuteserrata)树干液流密度的影响 DOI: 10.5846/stxb201903060423 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国际竹藤中心基本科研业务费专项基金项目（1632018002，1632018004，1632017016）；国家重点研发计划（2018YFC0507301） Effects of manipulated throughfall reduction on sap flux density of Quercus aliena var. acuteserrata Author: Affiliation: Fund Project: International Bamboo and Rattan Center"s special funds for basic research and operation fees;National Key R&D Program 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:降水格局变化是全球气候变化的重要特征之一，未来气候变化下，较为频繁和严峻的干旱将威胁地球中纬度部分地区的森林，但森林植被如何响应季节性干旱胁迫及其机制尚不清楚。北亚热带-暖温带过渡区分布着以锐齿栎（Quercus aliena var. acuteserrata）为优势树种的落叶阔叶林，研究其水分蒸腾代谢过程对干旱的响应是评估气候变化对过渡区天然落叶阔叶林生态系统水碳影响的关键科学问题。在典型的锐齿栎天然林中通过开展模拟穿透雨减少大型野外实验，采用Granier热扩散式探针技术监测锐齿栎树干液流密度的动态变化，研究了不同径级锐齿栎树干液流密度对模拟干旱的响应规律。结果表明：（1）穿透雨减少对树干液流密度的影响呈现季节变异。在7月份，林内穿透雨减少显著降低了锐齿栎的树干液流密度，但生长季后期的10月份林内穿透雨减少反而使锐齿栎树干液流密度显著升高。（2）不同径级的锐齿栎树干液流密度在生长季内对干旱有不同的响应，特别是小径级的树干液流密度与其他径级有较多的不同。小径级的锐齿栎树干液流密度在5、7月份表现为减雨样地显著小于对照样地，在9、10月份则表现为减雨样地显著大于对照样地。中径级的锐齿栎树干液流密度在5、10月份表现为减雨样地显著大于对照样地，在7月份则表现为减雨样地极显著小于对照样地。大径级的锐齿栎树干液流密度在6、7月份表现为减雨样地显著小于对照样地，在10月份则表现为减雨样地显著大于对照样地。 Abstract:The change in precipitation pattern is one of the characteristics of global climate change. Some regions at mid-latitude might experience more frequent and severe drought. However, it is unclear how the precipitation change will affect the forest vegetation in those regions. Amongst, Quercus aliena var. acuteserrata is the dominant canopy tree species of deciduous broad-leaved forests in the warm temperate zone of middle China. Understanding the evapotranspiration responses of Q. aliena to drought induced by climate change is crucial to elucidate carbon-water coupling process. In order to explore the warm-temperate deciduous broad-leaved forest response to precipitation change, a manipulated throughfall reduction experiment was conducted in Baotianman National Nature Reserve since 2013. The Granier thermal diffusion probe (TDP) was used to measure the dynamic change of sap flux density of Q. aliena. The results showed that the throughfall reduction had significant effects on the sap flux density (Js) during the growing season. Firstly, the throughfall reduction significantly reduced the sap flux density of Q. aliena in July. However, in the late growing season (October), the throughfall reduction increased the sap flux density of Q. aliena significantly. Therefore, the sap flux density of Q. aliena differently responded to the throughfall reduction among months during the growing season. Secondly, the sap flux density of Q. aliena of different tree sizes showed different responses to drought during the growing season, especially the small trees (diameter at breast height, DBH≤21 cm) was different from that of medium (21 cm 参考文献 相似文献 引证文献

Contrasting drought impacts on the start of phenological growing season in Northern China during 1982–2015

AbstractDrought is a widely occurring extreme climatic event that may have various effects on vegetation phenology and activity. The change of the start of the phenological growing season (SOS) is one key mechanism for ecosystem responses to droughts yet remain unknown at large scale. This study used abnormal changes in the ratio of reference evapotranspiration (ETO) and precipitation (P) to detect the pre‐season (defined as the 3 months before the growing season) monthly drought during 1982–2015. After that, the pre‐season drought impacts on SOS were analysed. Drought appeared frequently (>3.6 times/10 years) in the northern and southwest China, as well as the coastal area of south China during the last 34 years. The droughts generally accompany a higher temperature and a stronger radiation, but the drought effects on the SOS differ between humid/sub‐humid and semi‐arid zones in northern China. Specifically, in the temperate humid/sub‐humid zones, SOS under drought was 1.08–4.86 days earlier than during normal (no drought) years, and the response was greater to the droughts that appeared in the first two of the three pre‐season months. In addition, in the cold, mid‐, and warm temperate zones, the advance response was more concentrated in the SOS about DOY130‐140, DOY125‐150, and DOY80‐160, respectively. However, in the north semi‐arid zone, the SOS under drought was 0.66–3.45 days later than during normal years, and the response was greater to the droughts that appeared in the last two of the 3 months. These delay responses also concentrated in the SOS about DOY125‐150. The contrasting drought impacts on phenology suggest that we should move beyond the vegetation activity under droughts such as the growth, productivity, and mortality, and pay more attention to the timing of vegetation activity to better quantify the carbon budget at Northern Hemisphere.

Middle Jurassic Plant Diversity and Climate in the Ordos Basin, China

The Ordos Basin is one of the largest continental sedimentary basins and it represents one major and famous production area of coal, oil and gas resources in China. The Jurassic non-marine deposits are well developed and cropped out in the basin. The Middle Jurassic Yan’an Formation is rich in coal and contains diverse plant remains. We recognize 40 species in 25 genera belonging to mosses, horsetails, ferns, cycadophytes, ginkgoaleans, czekanowskialeans and conifers. This flora is attributed to the early Middle Jurassic Epoch, possibly the Aalenian-Bajocian. The climate of the Ordos Basin during the Middle Jurassic was warm and humid with seasonal temperature and precipitation fluctuations. The result tends to support the palaeophytogeographic/palaeoclimatic setting of the Ordos Basin in the North Floristic Province, or the North Chinese Province in the warm temperate zone during the Middle Jurassic.

Current and future patterns of forest fire occurrence in China

Forest fire patterns are likely to be altered by climate change. We used boosted regression trees modelling and the MODIS Global Fire Atlas dataset (2003–15) to characterise relative influences of nine natural and human variables on fire patterns across five forest zones in China. The same modelling approach was used to project fire patterns for 2041–60 and 2061–80 based on two general circulation models for two representative concentration pathways scenarios. The results showed that, for the baseline period (2003–15) and across the five forest zones, climate variables explained 37.4–43.5% of the variability in fire occurrence and human activities were responsible for explaining an additional 27.0–36.5% of variability. The fire frequency was highest in the subtropical evergreen broadleaf forests zone in southern China, and lowest in the warm temperate deciduous broadleaved mixed-forests zone in northern China. Projection results showed an increasing trend in fire occurrence probability ranging from 43.3 to 99.9% and 41.4 to 99.3% across forest zones under the two climate models and two representative concentration pathways scenarios relative to the current climate (2003–15). Increased fire occurrence is projected to shift from southern to central-northern China for both 2041–60 and 2061–80.

The Impacts of Human Activities on Ecosystems within China’s Nature Reserves

Protected areas (PAs) provide refuges for threatened species and are considered to be the most important approach to biodiversity conservation. Besides climate change, increasing human population is the biggest threat to biodiversity and habitats in PAs. In this paper, the temporal and spatial variations of land cover changes (LCC), vegetation fraction (VFC), and net primary productivity (NPP) were studied to present the ecosystem dynamics of habitats in 6 different types of national nature reserves (NNRs) in 8 climate zones in China. Furthermore, we used Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light datasets and the human disturbance (HD) index estimated from LCC to quantify the living and developing human pressures within the NNRs in the period 2000–2013. The results showed that (1) the living human activities of NNRs increased apparently in the humid warm-temperate zone, Qinghai-Tibet Plateau, mid-temperate semi-arid zone, and mid-temperate humid zone, with the highest increase of nighttime light observed in inland wetlands; (2) the developing human activities in NNRs indicated by the HD index were higher in the humid warm-temperate zone and mid-temperate semi-arid zone as a result of increasing areas of agricultural and built activities, and lower in the sub-tropics due to improved conservation of forest ecosystems; (3) the relationship between HD and VFC suggests that ecosystems in most NNRs of south-subtropics, mid-temperate arid zone and Qinghai-Tibet Plateau were predominantly impacted by climate change. However, HDs were the prevalent factor of ecosystem dynamics in most NNRs of north-subtropics, mid-temperate semi-arid and humid zones.

Size-based intraspecific variations along altitudinal gradient and follow of Bergmann’s rule in Parthenium beetle, Zygogramma bicolorata Pallister

Abstract Body size in insects is coupled with numerous physiological, life-history and ecological traits. Its variation along temperature gradient is widely studied. However, information regarding variations in body size of insects along altitudinal gradient is limited. Present study was designed considering hypothesis that there would be an increase in body size of Parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) with increasing altitude and decreasing in temperature. To achieve the objectives, beetles were collected from three eco-climatic zones of NEPAL [Kathmandu (1400 mts, 24 °C; warm temperate zone), Chitwan (415 mts, 25 °C; upper tropical/sub-tropical zone), and Mahendranagar (229 mts, 34 °C; humid subtropical zone)], and one of INDIA [Varanasi (81 mts, 36 °C; humid subtropical zone)] for their morphometric analysis (body length and body biomass). Results revealed that the size of beetles in all eco-climatic zones increased with increasing altitude and decreasing temperature. While adults of Kathmandu were largest, followed by Chitwan and Mahendranagar, but those of Varanasi were smallest in size. The sex ratio was female-biased in Kathmandu and Varanasi, but was male-biased in Chitwan and Mahendranagar. Irrespective of temperature and altitude, females were larger than males in all eco-climatic zones. Our results affirmed our hypothesis and were in compliance with Bergmann’s rule. The findings may be helpful in understanding phenotypic plasticity and distribution pattern of Z. bicolorata adults in Indian sub-continent under global climate change scenario.

Do Coarser Gap Mosaics in Conifer Plantations Induce More Seed Dispersal by Birds? Temporal Changes during 12 Years after Gap Creation

The creation of canopy gaps is thought to be an efficient silvicultural operation to diversify species composition of monoculture conifer plantations; however, the shortage of regeneration materials in overclosed plantations is one of the concerns related to this operation. Seed dispersal by frugivorous birds may play an important role in inducing the spread of native broad-leaved trees in canopy gaps in plantations in the warm temperate zone of central Japan because bird-dispersed woody species are abundant in this area. We monitored the dynamics of the abundance and species composition of bird-dispersed seeds over 12 years after gap creation in the canopy of a Japanese cypress (Chamaecyparis obtusa (Siebold et Zucc.) Endl.) plantation. We also studied the effects of gap-mosaic patterns (from many small gaps to fewer large gaps) on dispersal. We used a hierarchical Bayesian zero-inflated Poisson model to analyze the factors affecting seed dispersal by frugivorous birds. Seed dispersal by birds increased with gap age except for just after gap creation. Dispersal in coarser gap mosaics was more abundant than that in finer gap mosaics. The species diversity of dispersed seeds in each seed trap (α-diversity) and plot (γ-diversity) showed similar trends in terms of temporal changes and differences between plots related to seed dispersal abundance; β-diversity did not. These trends might have been caused by shrub-vegetation development after gap creation. The effects of shrub vegetation were classified into the attraction by fruits borne within the vegetation, as well as other effects related to vegetation, such as functions of perch availability and insect presence as a food source. The presence of bird-dispersed seeds was strongly promoted by vegetation in all seasons, but only marginally by the presence of fruit-bearing vegetation. However, fruits attracted seed dispersal by frugivorous birds in the winter season. Our results suggest that both vegetation development and fruiting are important for promoting seed dispersal by frugivorous birds, and those effects are different in different seasons according to vegetation conditions and shifting food resources.

Study on Working Pairs of Sorption Type Air Conditioner for Electric Vehicles under Different Temperature Zones

The air conditioning (AC) system of electric vehicles (EVs) consumes a large part of electricity of on-board batteries and influences the continue voyage course seriously. The feasibility of sorption type AC for EVs has been verified theoretically to decrease this part of energy consumption. However, the choice of optimal working pairs based on local working conditions is not considered before, which can realize not only high efficiency but also the steady and reliable operation. Thus in this paper, different solid sorption working pairs used in sorption type AC under different temperature zones are studied. We utilized Rubotherm balance test unit to study the sorption properties of various working pairs (halide-ammonia) and selected candidate working pairs by Clapeyron equation and energy analysis. Results show that MnCl2 is the only choice for cold temperate zone (CTZ) and CaCl2 is optimal for warm temperate zone (WTZ), while the mixed double halide (MnCl2 and CaCl2) is recommended in other zones. In middle temperate zone (MTZ), the probability for performance dropping down is relatively large, thus the ratio (CaCl2:MnCl2) is recommended as 0.33-1 to take advantage of the stability property of MnCl2. While in Qinghai-Tibet plateau cold area (QTPCA, the special temperature zone in China), the ratio is chosen as 2–3 because only under the limiting condition reaction [Ca(NH3)8]VCl2 ⇔ [Ca(NH3)4]Cl2+4NH3 is invalid. Because the continued high environmental temperature will increase the probability of limiting condition, ratio of subtropical zone (STZ) is still selected as 2–3 while that of tropical Zone (TZ) is 1–2. Taking WTZ under summer condition as example, by using sorption type AC with CaCl2 as sorbent, the increment voyage course (IVC) over the practical voyage course with conventional compression AC system (PVC) ranges from 9.4% to 37.7% for different type of EVs, i.e. the continue voyage course is increased effectively. This work provides the guidance for choosing optimal working pairs for actual utilization.

Comparison of surface and canopy urban heat islands within megacities of eastern China

Urban heat island (UHI) can be characterized and quantified to understand the modification of urban surfaces on the local and regional climate. This study examines UHI variation across three megacities that are located in rapid urbanization regions in eastern China (Beijing, Shanghai and Guangzhou). These cities are located within a warm temperate climate zone, north subtropical climate zone, and lower subtropical climate zone, respectively. Satellite-based land surface temperature (LST) data and air temperature records from 2003 to 2016 were used to identify surface urban heat island (SUHI) and canopy urban heat island (CUHI), respectively. Generally, the average annual SUHI is higher than the CUHI, with the greatest UHIs appearing in Beijing (SUHI: 2.33 ± 0.18 °C, CUHI: 1.45 ± 0.54 °C). UHI changes across latitudes were negatively related to humidity variation, with higher UHI in drier climates. Seasonal UHI analysis suggests that a lower SUHI would occur in winter and a higher UHI in spring and summer, except for Guangzhou. CUHI in dry season was higher than in wet season for all three megacities, and the largest CUHI (2.10 ± 0.33 °C) appeared in winter in Beijing. Various patterns of seasonal cycles of SUHI and CUHI were related to monthly precipitation and solar insolation. Annual average daytime SUHI was higher than the nighttime SUHI, and larger daytime SUHI appeared in Guangzhou, contrasting with Shanghai and Beijing. The difference between SUHI and CUHI for all seasons was also high in Guangzhou. UHI changes were considered to be altered by warm and wet conditions in mega-cities of eastern China, and heat transportation from urban surface to urban canopy provided some possible understanding of the UHI change.

GREEN LIVING ROOF SIMULATION MODEL REVIEW

Integration of nature, live, organic materials, in the design of built areas and building structure is an architectural response to environmental problems of dense urban areas. At the site where green space is limited, greening the building envelope is the solution for the issues such as heat waves, flooding, and noise and air pollution. The benefits could be predicted only using accurate simulation model of this technology. The energy balance of green living roof was researched through models developed over the years by various authors. Most models have been developed and validated with data from extensive roofs and more than 50% of the models were validated using data from warm temperate climatic zones. Ability to determine the impact of green living roofs at different stages of their architectural design process is of most importance if the incorporation this technology is planned due to the impact on building and urban level.

Changes of vegetation in southern China

In order to reveal the changes of vegetation in southern China since the Last Glacial Maximum, we have established high-resolution time scales and palynological sequences of borehole profiles by drilling cores in some weak areas of the research to restore vegetation changes over the past 20,000 years on the basis of previous work. This paper gives the vegetation zoning maps of 18, 9 and 6 ka BP respectively in southern China, and describes the distribution characteristics of plants in different zones/subzones. The results show that the vegetation zonations around 18 ka BP were significantly different from that at present. It appeared in turn with Cold-temperate coniferous forest and alpine meadow steppe zone, and Temperate mixed coniferous and broad-leaved forest zone/warm temperate deciduous broad-leaved forest zone from northwest to southeast in the west, and Temperate mixed coniferous and broad-leaved forest zone, Warm temperate deciduous broad-leaved forest zone, and Northern subtropical mixed evergreen and deciduous broad-leaved forest zone from north to south in the central and east. The vegetation distribution around 9 ka BP changed distinctively. Except that the northwest part was located in Mountain temperate mixed coniferous and broad-leaved forest zone, the vegetation in other areas occurred in turn with North subtropical mixed evergreen and deciduous broad-leaved forest subzone, Mid-subtropical typical evergreen broad-leaved forest subzone, and South subtropical monsoon evergreen broad-leaved forest subzone/Tropical seasonal rainforest and rainforest zone from north to south. There was little change in the appearance of vegetation zonations between 6 and 9 ka BP, but the northern edge of each vegetation belt moved a little northward, reflecting that the overall climate became warmer around 6 ka BP. The vegetation changes in southern China over the past 20,000 years were largely driven by environmental changes. Climate change was the main factor affecting the vegetation distribution. The impact of human activities became more and more remarkable in the later period. In the lower reaches of the Yangtze River and the delta region, sea level changes also influenced the vegetation distribution.

Dynamic Changes in the Wetland Landscape Pattern of the Yellow River Delta from 1976 to 2016 Based on Satellite Data

The Yellow River Delta wetland is the youngest wetland ecosystem in China’s warm temperate zone. To better understand how its landscape pattern has changed over time and the underlying factors responsible, this study analyzed the dynamic changes of wetlands using five Landsat series of images, namely MSS (Mulri Spectral Scanner), TM (Thematic Mapper), and OLI (Operational Land Imager) sensors in 1976, 1986, 1996, 2006, and 2016. Object-oriented classification and the combination of spatial and spectral features and both the Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI), as well as brightness characteristic indices, were used to classify the images in eCognition software. Landscape pattern changes in the Yellow River Delta over the past 40 years were then delineated using transition matrix and landscape index methods. Results show that: 1) from 1976 to 2016, the total area of wetlands in the study area decreased from 2594.76 to 2491.79 km2, while that of natural wetlands decreased by 954.03 km2 whereas human-made wetlands increased by 851.06 km2. 2) The transformation of natural wetlands was extensive: 31.34% of those covered by Suaeda heteropteras were transformed into reservoirs and ponds, and 24.71% with Phragmites australis coverage were transformed into dry farmland. Some human-made wetlands were transformed into non-wetlands types: 1.55% of reservoirs and ponds became construction land, and likewise 21.27% were transformed into dry farmland. 3) From 1976 to 2016, as the intensity of human activities increased, the number of landscape types in the study area continuously increased. Patches were scattered and more fragmented. The whole landscape became more complex. In short, over the past 40 years, the wetlands of the Yellow River Delta have been degraded, with the area of natural wetlands substantially reduced. Human activities were the dominant forces driving these changes in the Yellow River Delta.

Investigating Surface Urban Heat Islands in South America Based on MODIS Data from 2003–2016

Surface urban heat islands (SUHIs) have been investigated in many regions around the world, but little attention has been given with regard to SUHIs in South America. In this study, Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) data was used to investigate the diurnal, seasonal, and interannual variations in the SUHI intensity (SUHII, the urban LST minus the rural LST) in 44 South American cities in different climate zones and types of rural land. To examine the effects of factors that may influence the SUHII, correlations between the SUHII and the enhanced vegetation index (EVI), urban area, population, altitude, and anthropogenic heat emissions were performed. The results showed that the SUHI effect was obvious in South America. The mean daytime SUHII was higher than the mean night-time SUHII in all areas except for the arid climate zone. In the daytime, the summer displayed a stronger SUHII in the warm temperate climate zone than the other seasons. The night-time SUHII showed less obvious seasonal variations. In addition, the surrounding land cover influenced the SUHII. During the day, the SUHII was therefore stronger in rural areas that were covered by forests than in other types of rural land. Interannually, most cities showed an insignificant temporal trend in the SUHII from 2003 to 2016. The daytime SUHII was significantly and negatively correlated with the ∆EVI (the urban EVI minus the rural EVI) across the 44 cities, but a poor relationship was observed at night. In addition, anthropogenic heat emissions were positively correlated with the night-time SUHII. Urban area, population, and altitude were weakly correlated with the SUHII, which suggested that these factors may not have a significant impact on the spatial variations in the SUHII in South America.

Aquatic mesocosms exposed to a fungicide in warm and cold temperate European climate zones: Long-term macroinvertebrate response

At present, the European Union legislation facilitates the use of similar pesticides among European Member States, thereby assuming that biodiversity and ecosystems have equal sensitivities to contaminants throughout the whole of Europe. However, with this assumption, fundamental environmental and biological differences between climatic zones are being ignored in Environmental Risk Assessment. Such differences may strongly influence the behaviour of contaminants, their effects on biodiversity and on the natural functioning of ecosystems. Furthermore, toxicity testing in European ecoregions other than cold-temperate has largely depended on standardized tests using cold-temperate species and conditions, which may lead to a false estimation of risks to organisms from other ecoregions. The present study aim was to determine the response of freshwater macroinvertebrate communities to the fungicide pyrimethanil by conducting aquatic mesocosm experiments in two different ecoregions with different climates: cold-temperate (Frankfurt, Germany) and warm-temperate (Coimbra, Portugal). The results indicate that the community in the cold-temperate climate was more sensitive to the fungicide in comparison to the warm-temperate community. This difference was most likely related to a different rate of fungicide disappearance, which was slower in the colder climate. Based upon our results we discuss important implications for improving Environmental Risk Assessment across climate zones and under present-day global climate change scenarios.

Optimization of black soldier fly (Hermetia illucens) artificial reproduction.

The black soldier fly (BSF), Hermetia illucens (L., 1758) (Diptera: Stratiomyidae), is an endemic fly species from the tropical, subtropical and warm temperate zones of America. This saprophagous species relies on its environment where it finds the decomposing matter for the larvae to grow. The polyphagous diet and the macronutrient quality (mainly lipids and proteins) of these larvae make them excellent candidates for various applications such as waste and organic material management, incorporation in animal feed or alternative energy source. Although rearing development in temperate regions requires artificial processes to continuously produce high quality eggs and larvae, few studies have been conducted on the mating and oviposition processes governing H. illucens reproduction. Research conducted in semi-artificial rearing conditions showed that the number of mating varied according to the season. It has been speculated that this behavior could be due to differences in the intensity of sunlight caused by the change of seasons. This study aims at evaluating the influence of sex-ratio, density and nycthemeral cycle on H. illucens reproduction. In order to tackle this issue, an artificial set up for oviposition to collect eggs has been developed. This egg collection system aims at centralize oviposition and simplify eggs collection. Two populations with opposite sex-ratio (male-dominant and female-dominant) were selected. Their respective eggs productions have been evaluated for five breeding densities. Eggs weights varied significantly among the densities for each opposite sex-ratio population and female dominant population produced most eggs weight from 6500 individuals /m3. Finally, four nycthemeral cycles (2, 6, 12 and 18h of daily light) were simulated to evaluate the impact of light duration on reproduction. Early oviposition pic associated with a decrease of the oviposition period are shown when H. illucens are exposed to increasing light duration. These experiments enable improvement of the understanding on artificial reproduction of H. illucens.

Habitat utilization by an intertidal isopod, Dynoides dentisinus Shen, 1929 (Isopoda, Sphaeromatidae)

Abstract Intertidal isopods use a variety of living or non-living objects as habitats, although only a few studies have been made on their ecological function and significance. In the present study, the habitat utilization by the sphaeromatid isopod, Dynoides dentisinus was recorded based on observations on intertidal rocky shores in the warm temperate zone of Japan during the period from 2014 to 2018. The adults of this species have a remarkable sexual dimorphism in the morphology of their armature: adult males possess an elongate pleonal process, like a large horn, on the dorsal side of the pleon and have large uropods. On the other hand, females do not have such a horn, and the uropods are small. Differences in habitat use were seen according to the stage in the life history of the species. Juveniles lived on, or amongst, algae and were sometimes associated with molluscs such as chitons, limpets and whelks. Adults inhabited the cryptic habitats such as gaps in algal holdfasts, oscula of demosponges, dead barnacle shells, cavities of dead corals, and crevices in sand rocks. Generally, a single adult male was present in each cryptic habitat, keeping head in down position, and one or more females cohabited inside with the male. These suggest that D. dentisinus has a biphasic life history; juveniles live and feed on algal cover or use the spaces between the ventral sides of the molluscs and the surfaces of the rocks as a refuge from desiccation. Adults breed in the cryptic habitats, forming a polygynous group.

Development and characterization of EST-SSR markers for Vitex negundo var. heterophylla (Lamiaceae).

Premise of the Study Vitex negundo var. heterophylla (Lamiaceae) is a dominant shrub in the warm temperate zone of northern China. Expressed sequence tag–simple sequence repeat (EST‐SSR) markers were developed to investigate its genetic diversity and structure.Methods and ResultsWe detected 12,075 SSRs in V. negundo var. heterophylla using transcriptome sequencing. Primer pairs for 100 SSR loci were designed and amplified in three populations of V. negundo var. heterophylla. Sixty loci were amplified, of which 14 were polymorphic. The number of alleles per locus ranged from two to 15, and levels of observed and expected heterozygosity ranged from 0.241 to 0.828 and from 0.426 to 0.873, respectively. All primer pairs amplified PCR products from V. rotundifolia but only four of them amplified products from Leonurus japonicus.ConclusionsThe identified EST‐SSR markers will be useful for future molecular and reproductive ecology studies of V. negundo var. heterophylla and V. rotundifolia.

Spring Phenological Grid Dataset of Eight Deciduous Broad-leaved Woody Plants in the Warm Temperate Zone of China (1963–2015)

Spring Phenological Grid Dataset of Eight Deciduous Broad-leaved Woody Plants in the Warm Temperate Zone of China (1963–2015)