重庆秋马铃薯适宜播种期试验初报

近年来极端气候事件频发,在气候变化背景下合理高效利用秋季气候资源,对重庆晚秋生产具有重要意义。采取分期播种试验方法,探讨重庆地区秋马铃薯适宜播种期。结果表明:受试验当年8月上中旬高温和秋棉雨的影响,8月27日播种的出苗率最高,8月27日至9月11日播种的秋薯商品率最高,9月11日播种的产量最高。结合重庆地区晚秋气候特点、耕作制度以及马铃薯的品种特性,认为重庆350m以上地区秋马铃薯宜8月中旬播种,350m以下地区宜8月下旬播种。     

重庆地区芥菜高产栽培技术

芥菜适合炒食和淹渍,重庆地区芥菜需求量大。文章针对重庆气候环境,总结介绍重庆地区芥菜高产栽培技术,以期对生产实践有所指导。     

重庆市果树研究所部分新优油桃及桃品种简介

重庆冬季气候温暖,有的桃品种休眠期需冷量不能得到正常满足,表现出萌芽、开花不正常,落花落果严重,无产量或不能连年丰产.随着全球气候变暖、三峡工程的实施,重庆地区冬季气温将明显上     

重庆园林特色分析

重庆园林的主要影响因素以地形地貌因素为主。文章主要分析重庆地区的园林特色,并通过具体的实例阐述重庆园林建筑物特点、理水特点和植物种植特点。     

李优质绿色高效配套技术

针对重庆地区高温多湿的气候特点,总结了李土肥水管理、控冠促花,以及病虫害绿色防控技术,为李优质绿色高效益生产提供技术参考。     

重庆地区糯玉米产业化探讨

分析了重庆发展糯玉米产业的必要性和可行性、重庆地区糯玉米种植现状及存在的问题，提出重庆发展糯玉米的主攻方向。     

重庆市地区核心竞争力评价与对策分析

站在如何建立城乡统筹发展新特区的角度,运用定性定量相结合的分析方法,通过建立地区核心竞争力评价系统,对重庆地区核心竞争力的现状、问题及重庆在全国所处的位置进行了深入细致的分析,并提出了提升重庆地区核心竞争力的对策与建议,希望能够对加快重庆全面小康社会进程起到一定的催化作用。     

重庆丘陵橘园水分管理问题及解决的途径

根据柑橘对水分的一般要求，结合重庆地区特有的气候环境，从理论和实践结合的角度，探讨通过主动抗旱，充分满足橘园周年水分需求的可行性及解决途径，并对橘园水分管理的科学化、自动化等提出一些看法。     

锦屏藤在重庆地区的引种栽培初步

锦屏藤在长江流域多生长于农业观光园区的温室内。作者于2009年春季开始在重庆栽培锦屏藤植株,目前已通过环境适应性考验,认为可以在重庆地区有选择性地推广应用。文章初步总结了重庆地区锦屏藤的引种栽培经验。     

重庆地区适栽油桃引种报告

油桃果面光滑无毛、色彩艳丽,已成为世界鲜食桃品种改良的主要方向。近年,我国油桃发展迅猛,已由北向南逐步推广,但在南方地区,如四川、重庆、湖南、湖北、广西等地发展油桃,在考虑必须满足品种需冷量的同时,还要选择抗裂果、着色好、味甜的油桃品种。重庆地处四川盆地东部,温度高,湿度大,具有典型的南方气候特点。为了找到重庆地区适栽油桃品种,重庆市林业果树研究所于1999年引进了双红、中油5号、中油4号、燕红11号、曙光、艳光、瑞光3号等10余个国内优良油桃品种,当年冬天定植于重庆市正邦现代农业有限公司(以下简称正邦公司)果树示范基…     

Urban-rural and temporal differences of woody plants and bird species in Harbin city,northeastern China

Urbanization has been greatly accelerated by the economic growth in China, while its possible effects on woody plants, bird species and their associations are not well defined yet. Here, we analyzed urban-rural gradients (landscape level: urban-farmland-forest-natural reserves; city level: ring road and urban build-up history) and temporal data (1955–1980–2014 for woody plants; 1980s–2010 s for birds) in Harbin city, China, to investigate the changes in the composition and diversity of woody plants and birds during urbanization. Both landscape gradient and temporal data confirmed that urbanization had the function of species conservations with sharp increases of alien species and tropical type plants. In the case woody species, 60-yr urbanization in Harbin had induced increases of 9 families and 17 genera, and there were 7–20 more families, 12–35 more genera, 1.6–2.6 higher Margalef richness in urban areas than those in nature reserves and local forest farms; Increases in alien species (4-fold in 60-yr urbanization; 21% in urban area vs <2% for non-urban region) and tropical type plants (1.6-fold in 60-yr urbanization; temperate/tropical ratio at 1.2 in urban area vs >1.6 in non-urban area) were mainly responsible for these compositional changes, which can be proved by their significant correlations. Moreover, moderate disturbance had peak values in alien species, tropical type plants, Shannon-wiener diversity, Margalef richness index and Pielou evenness index, and both ring road- and buildup history gradients showed the similar tendency. Compared with those in 1980s, forest- and eurytopic-habitats birds increased 9–11 species (23–39%), and omnivorous, insect-eating, and phytophagous bird increased 5–9 species (14.1–29.4%) in those in 2010s, indicating that bird temporal changes were closely related with the changes in urban forests owing to food supply and habitat provision. Our findings could provide data for biodiversity evaluation of urbanization effects, and is also useful for ecological re-construction of local cities in China.     

Efficient cooling of cities at global scale using urban green space to mitigate urban heat island effects in different climatic regions

In the context of rapid urbanization and global warming, how to use urban green space (UGS) with high-efficiency to mitigate the urban heat islands (UHIs) effect in different climate zones has become an urgent issue. However, few studies have provided specific guidance for urban vegetation planning adapting to different climate zones on a global scale. In this study, a cooling effect framework was employed to analyze the influence of UGS patch characteristics, natural and anthropogenic factors on its cooling effect across different climatic zones. We found that the urban cooling islands (UCI) intensity, extent, and gradient of UGS increased with latitude, with lower cooling effect concentrated in arid zones around 30 °N, while the largest (0.38 ha) and smallest (0.24 ha) threshold value of efficiency (TVoE) were found in the temperate and arid climate zones. The larger the UGS area, the better the cooling effect in all climate zones. Moreover, complex shapes have a greater UCI intensity in tropical and temperate zones than other regions, while the normalized difference vegetation index (NDVI) has a stronger effect in arid zones. In the continental zone, patch characteristics had little effect. The overall explanation rate of natural and anthropogenic factors on the cooling effect of UGS was 53.5 %, among which natural factors were approximately twice that of anthropogenic factors. Notably, natural factors dominated in the tropical and arid zones affecting UCI, and anthropogenic factors dominated in the temperate and continental zones. The findings of this study expand our understanding of the cooling effect of UGS in different climatic zones around the world and provide insights for urban sustainable development.     

Reactions of strawberry plants to long-term freezing and alternate freezing and thawing

Summary

The study was conducted in two experiments, one examining the effects of alternate freezing and thawing at –12?C for 2 h and +6#x02DA;C for 24 h, and the other examining the effects of permanent freezing for 1 or 15 d at+12?C. In both experiments the plants were grown in the pre-fruiting period at a coastal or a continental location in Norway. The freezing injury increased the higher the stress, indicated by reduced growth, fruit size and yield.It was shown that ‘Korona’ was the most hardy cultivar at a short period of freezing stress and at alternate freezing and thawing, while ‘Senga Sengana’ was more freezing tolerant at long-term permanent freezing than ‘Bounty’ and ‘Korona.’ In general the results indicate that the plants induce freezing tolerance according to some factor of origin, since plants grown in the continental climate were better able to survive long-termpermanent freezing than plants grown in a coastal climate, and plants grown in a coastal climate were better able to survive alternate freezing and thawing than plants grown in a continental climate.     

热带雨林低光植物结构色产生机制及生物学功能研究进展

 生长在热带雨林低光环境中的林木植被部分叶片表面呈现蓝晕色表型。这种蓝晕色表型由叶片表皮附近多种相同或相异的微结构所引起。各种微结构是植被适应低光生长环境而长期进化的产物。它通过改变植物组织内部反射光的物理特性，在增强光合活性光吸收的同时产生蓝晕色或其它周期性变化的复合色，从而形成植物结构色表型。结构色的存在在植物生长发育过程中起到关键作用。本文综述了植物结构色产生的机制以及生物学功能。     

试论景洪热带地区园林植物造景的特点

对景洪热带地区独有的少数民族,结合当地自然风貌,尝试将景洪热带地区总结出人与大自然植物景观和谐相处,重视"意"与"匠"的结合,傣族民间园林植物造景与园林其它要素的结合,公园的植物造景特色,重视热带景观的营造5个植物造景的特点,对其进行了分析,并对热带地区园林植物造景研究的意义提出看法.     

Wetlands, carbon, and climate change

Wetland ecosystems provide an optimum natural environment for the sequestration and long-term storage of carbon dioxide (CO₂) from the atmosphere, yet are natural sources of greenhouse gases emissions, especially methane. We illustrate that most wetlands, when carbon sequestration is compared to methane emissions, do not have 25 times more CO₂ sequestration than methane emissions; therefore, to many landscape managers and non specialists, most wetlands would be considered by some to be sources of climate warming or net radiative forcing. We show by dynamic modeling of carbon flux results from seven detailed studies by us of temperate and tropical wetlands and from 14 other wetland studies by others that methane emissions become unimportant within 300 years compared to carbon sequestration in wetlands. Within that time frame or less, most wetlands become both net carbon and radiative sinks. Furthermore, we estimate that the world’s wetlands, despite being only about 5–8 % of the terrestrial landscape, may currently be net carbon sinks of about 830 Tg/year of carbon with an average of 118 g-C m^?2 year^?1 of net carbon retention. Most of that carbon retention occurs in tropical/subtropical wetlands. We demonstrate that almost all wetlands are net radiative sinks when balancing carbon sequestration and methane emissions and conclude that wetlands can be created and restored to provide C sequestration and other ecosystem services without great concern of creating net radiative sources on the climate due to methane emissions.     

Pollination management for controlled hybridization of white yam

Pollination and fertilization success in white yam, Dioscorea rotundata Poir., depend on knowledge and good management of factors influencing the availability of open male flowers from which good pollen can be collected for effective use in pollinations of genetically compatible female plants under non-xeric conditions. In vitro germination of pollen from numerous genotypes demonstrated varied viability (0.3–85.0%). However, pollen from bisexual flowers on monoecious plants was inferior to pollen from unisexual flowers from dioecious plants. Natural pollination by thrips is inefficient, such that populations with higher ratios of male to female plants set more fruits. To improve fruit set, hand pollinations should be made with pollen from diverse genotypes, early in the flowering period when net water balance is positive. In crossing-blocks, male plants should be closely interpositioned with female plants to reduce pollination distance, thereby improving pollination and fruit set.     

Application of thermal sums concept to estimate the time to harvest new banana hybrids for export

Application of the thermal sum concept was developed to determine the optimal harvesting stage of new banana hybrids to be grown for export. It was tested on two triploid hybrid bananas, FlhorBan 916 (F916) and FlhorBan 918 (F918), created by CIRAD's banana breeding programme, using two different approaches. The first approach was used with F916 and involved calculating the base temperature of bunches sampled at two sites at the ripening stage, and then determining the thermal sum at which the stage of maturity would be identical to that of the control Cavendish export banana. The second approach was used to assess the harvest stage of F918 and involved calculating the two thermal parameters directly, but using more plants and a longer period. Using the linear regression model, the estimated thermal parameters were a thermal sum of 680 degree-days (dd) at a base temperature of 17.0 °C for cv. F916, and 970 dd at 13.9 °C for cv. F918. This easy-to-use method provides quick and reliable calculations of the two thermal parameters required at a specific harvesting stage for a given banana variety in tropical climate conditions. Determining these two values is an essential step for gaining insight into the agronomic features of a new variety and its potential for export.     

Characterization and inheritance of a bush-type in tropical pumpkin (Cucurbita moschata Duchesne)

A bush-type plant was selected from tropical pumpkin (Cucurbita moschata Duchesne) in order to study and compare the bush and vine habit of C. moschata in terms of various vegetative and reproductive characteristics. The bush plants were characterized by short internode and early days to anthesis, while the vine plants possessed more male flowers than the bush plants. Moreover, genetic analysis indicated that the bush plants have a monogenic inheritance, in which the bush genotype is dominant (Bu) to the vine genotype (bu). The measurement of hypocotyl growth and microscopic observation revealed that this bushy appearance is the result of cell elongation inhibition.     

合川巴渝新居庭院植物多样性分析

选择合川具有代表性的巴渝新居,对其庭院植物进行调查与群落多物种多样性分析。结果表明:在被调查的140户庭院中,共栽种161种植物,隶属于70科132属;种子植物的科属分布类型齐全,地理成分复杂多样,科和属的分布都以热带分布为主;对各村木本植物的丰富度、Simpson指数、Shannon-Wiener指数分析,古圣村多样性指数较高,山林村多样性指数较低;合川巴渝新居庭院植物生活型丰富,乔木与草本植物最多,而灌木与藤本较少。