海绵城市理念在南宁邕江综合整治工程中运用

以南宁市邕江综合整治工程为例,通过生态护岸、坡面绿化、道路铺设、水生植物种植等措施的综合应用,探讨河道治理与海绵城市建设的有效衔接,实现改善与保护城市水生态环境、节约水资源、保障水安全的有机统一。该设计对类似城市的河道整治工程设计有一定的参考作用。

PIONEER PLANTS FOR ECOSYSTEM RECOVERY IN DRAINAGE BASIN OF ERLONGSHAN RESERVOIR IN HEILONGJIANG PROVINCE, CHINA

This article reveals the ecological features and the theories and methods of introducing pioneer plants in the process of eco-restoring in different degenerative ecosystems in the drainage basin of Erlongshan Reservoir in Heilongjiang Province by systemically studying the deteriorative ecosystems and using recovery theory. The study shows that with the rise in degenerative degrees of the ecosystems, bio-species and bio-diversity sharply decrease in the study area and microclimate becomes warmer and drier in natural ecosystem. Therefore, we must attach importance to the construction of plants and biodiversity. In the study, different pioneer plants are selected for different degenerative ecosystems to restore and maintain the service functions of the ecosystems.

The Study of Alfalfa-Sinorhizobium meliloti Symbiosis Productivity under Different Water Conditions and the Influence of the Legume Seeds Lectin

The paper studies the effect of incubation of rhizobia with soybean seeds lectin on formation and functioning of alfalafa-Sinorhizobium meliloti symbiosis under the optimal water supply and drought conditions. It was shown that the addition of lectin to the inoculation compositions intensifies physiological processes in alfalfa plants： increases nitrogen fixing activity of symbiosis, nodule number on roots, as well as chlorophyll and carotenoid content in leaves, enhances plant growth during budding-fruiting period and reduces the negative effect of drought on alfalfa productivity.

The Effects of Cropping Methods on Growth, Crop Index and Yield Response to Water of Rice （Oryza sativa L.） in Rainfed Agriculture

In this study, four combinations of crops： rice （C）, rice-maize （MCSI）, rice-cassava （MCS2） and rice-maize-cassava （MCS3） with 3 m × 3 m each plots at two field areas--Saptosari and Tanjungsari were observed. Both field areas are located in Gunungkidul district, South-Central of Java Island, with that 93% at those areas are 185 m to 500 m above sea level and high proportion of multiple cropping systems （MCS）. The aim of this study was to investigate the effect of different cropping method on growth, crop index and yield response to water of rice in rainfed agriculture. Mathematical models were developed to describe rice growth. The rice height was followed monomolecular function and the number of tillers followed exponential polynomial function. Crop index was calculated from climate data during plant growth phase. And yield response to water was calculated from actual evapotranspiration （ETa） and the maximum evapotranspiration （ETm）. The results showed that the height of rice was not significantly different between each combination （P 〉 0.05）. Number of tillers was also not significant （P 〉 0.05）. However, monoculture treatment had more number of tillers than rice in MCS. Crop index of rice at Saptosari was higher than at Tanjungsari. Based on the calculation of evapotranspiration （ET）, water deficit at initial was less than at mid-season （ETa 〈 ETm） and affected water stress. Statistical analysis showed that cropping methods did not significantly affect rice growth and yield （P 〉 0.05）.

Magnetic field increase weight and water content in date palm （Phoenix dactylifera L.）

Magnetic field effects on different plant species have been subject of many studies in the last decade. Magnetic fields are known to induce changes in plant metabolism, growth and productivity. In this study, effect of magnetic field on date palm weight and water content has been investigated. Seedlings of date palm were treated with two types of magnetic fields in two separate experiments. In the first experiment, seedlings were treated with static magnetic field SMF using electromagnetic circuit set to produce three levels of magnetic field intensities 10, 50 and 100 mT for different durations （0, 30, 60, 120, 180 and 240 min）. In the second experiment seedlings were treated with alternating magnetic field AMF, using magnetic resonance imaging providing 1500 mT for 0, 1, 5, 10 and 15 min. After two months of exposure, plants growth parameters （fresh, dry weights and water content for both leaves and roots） were recorded. The measurements revealed that leaf fresh, dry weight and water content increased significantly in response to SMF treatment. Similarly, roots fresh weight and water content were increased significantly; however roots dry weight increasing were insignificant. In the second experiment, AMF has affected plant growth all parameters were increased significantly. Measurements reached the highest level at 15 min of exposure. This study revealed that magnetic fields affect date palm growth parameters by increasing osmotic pressure and water potential which increase water absorption and enhance flesh weight.

Self-renewal Capacity of Several Species of the Genus Sternbergia Possessing Medicinal Properties

The present work dealt with sexual reproduction capacity of three relic species of the genus Sternbergia （family AmaryUidaceae） distributed in the Caucasus, i.e., Sternbergia lutea （L.） Ker Gawl. ex Spreng., Sternbergiafischeriana （Herb.） Roem and Sternbergia colchiciflora Waldst. ＆ Kit.. Under this study, the natural populations of species, which possess valuable medicinal and ornamental properties, have been assessed by experts as vulnerable, and S. colchiciflora is included in the red list of endemic plants of the Caucasus, as having status of the critically endangered species. The situation is aggravated by the poor self-regeneration capacity of these species, which is one of the main factors responsible for the sustainability of the population of this or that species in the wild. Self-regeneration capacity for sexual reproduction was investigated in the listed species of the genus Sternbergia using common methods of embryology and reproduction biology. In conditions of the National Botanical Garden of Georgia （NBGG）, the species S. lutea and S. fischeriana prove to be completely infertile and propagate vegetatively by bulblets, while S. colchiciflora revealed the ability for propagation by seed. Long-term conservation of seeds of the studied species S. colchiciflora in the Caucasus Regional Seed Bank （CRSB） and establishing of living collections of this species at the experimental plot were chosen as the method for safeguarding this critically endangered species.

Responses of Soil Micro-Food Web to Land Use Change from Upland to Paddy Fields with Different Years of Rice Cultivation

Land use changes affect belowground ecosystems.During the past few decades,land use in Northeast China has changed considerably,and the area of paddy fields has increased rapidly from upland.In this study,soil characteristics and soil biotic community in paddy fields with different years of rice cultivation were measured to examine the effects of land use change from upland to paddy fields on soil micro-food web.The upland maize fields were selected as control and the microbial community composition was characterized using phospholipid fatty acids(PLFAs) analysis.The microbial biomass(total PLFA),bacteria biomass,and fungi biomass were higher in the 20-40-year(late-stage) than 1-10-year(early-stage) paddy fields.The abundances of total nematodes and bacterivores were lower in the early-stage than late-stage paddy fields.The abundance of herbivores was the highest in the early-stage paddy fields but that of omnivore-predators was the highest in the late-stage paddy fields.Structural equation model indicated that soil food web was developed and structured after 20 years of paddy cultivation.Our results suggested that soil micro-food web may be a good indicator for soil development and stabilization of paddy fields following land use change.

A buried Neolithic paddy soil reveals loss of microbial functional diversity after modern rice cultivation

It has been documented that human activities are causing the rapid loss of taxonomic, phylogenetic, genetic and functional diversity in soils. However, it remains unclear how modern intensive rice cultivation impacts the soil microbiome and its functionality. Here we examined the microbial composition and function differences between a buried Neolithic paddy soil and an adjacent, currently-cultivated paddy soil using high throughput metagenomics technologies. Our results showed that the currently cultivated soil contained about 10-fold more microbial biomass than the buried one. Analyses based on both 16S rRNA genes and functional gene array showed that the currently cultivated soil had significantly higher phylogenetic diversity, but less functional diversity than the buried Neolithic one. The community structures were significantly different between modern and ancient soils, with functional structure shifting towards accelerated organic carbon （C） degradation and nitrogen （N） transfor- mation in the modem soils. This study implies that, modern intensive rice cultivation has substantially altered soil microbial functional structure, leading to functional homogenization and the promotion of soil ecological functions related to the acceleration of nutrient cycling which is necessary for high crop yields.

The heart rate - breathing rate relationship in aquatic mammals： A comparative analysis with terrestrial species

Aquatic and semi-aquatic mammals, while resting at the water surface or ashore, breathe with a low frequency （f） by comparison to terrestrial mammals of the same body size, the difference increasing the larger the species. Among various interpretations, it was suggested that the low-f breathing is a consequence of the end-inspiratory breath-holding pattern adopted by aquatic mammals to favour buoyancy at the water surface, and evolved to be part of the genetic makeup. If this interpretation was correct it could be expected that, differently from f, the heart rate （HR, beats/min） of aquatic and semi-aquatic mammals at rest would not need to differ from that of terrestrial mammals and that their HR-fratio would be higher than in terrestrial species. Literature data for HR （beats/min） in mammals at rest were gathered for 56 terrestrial and 27 aquatic species. In aquatic mammals the allometric curve （HR=191 .M^18; M= body mass, kg） did not differ from that of terrestrial species （HR=212.M^-0.22） and their HR-fratio （on average 32±5） was much higher than in terrestrial species （5±1） （P〈0.0001）. The comparison of these HR allometric curves to those forfpreviously published indicated that the HR-fratio was body size-independent in terrestrial species while it increased significantly with M in aquatic species. The similarity in HR and differences in f between aquatic and terrestrial mammals agree with the possibility that the lowfof aquatic and semi-aquatic mammals may have evolved for a non-respiratory function, namely the regulation of buoyancy at the water surface [Current Zoology 61（4）： 569-577, 2015].

Intraspecific differentiation in seed flooding tolerance of Echinochloa crusgalli var.zelayensis population in shores of a giant reservoir along altitudinal gradients

Aims In a large dam-regulated reservoir with regular hydrological pattern and strong flooding gradients across shore elevations,plants inhabiting in different shore elevations have to confront long-lasting flooding of differential in tensities every year.Such persistent stress may lead to intraspecific differentiation of flooding tolerance in seeds.Echinochloa crusgalli var.zelayensis is a dominant annual plant in the shores of the Three Gorges Reservoir(TGR),which plays an important role in the shore vegetation.The objective of this study is to check whether intraspecific differentiation of seed flooding tolerance has occurred among E.crusgalli var.zelayensis populations in the TGR shores and whether such differentiation is associated with weak seed dispersal.Methods We collected seeds of E.crusgalli var.zelayensis from different populations in the TGR shores,and then placed them at four elevations in the shores flooded by reservoir impoundment.Parameters reflecting seed flooding tolerance including post-flooding percentage of intact seeds,seed germinability and seedling emergence rate were investigated for the seeds from different populations and undergoing flooding of different intensities.Floating time of seeds and speed of water level rise during impoundment were examined,and used to quantify dispersal potential of seeds in the shores of the TGR when flooded.Important Findings Both intact seed percentage and final seedling emergence rate after flooding significantly declined with increasing shore elevations where the seeds were collected,indicating that intraspecific differentiation in seed flooding tolerance has occurred among E.crusgalli var.zelayensis populations in the TGR shores after 7-year operation of the reservoir.The distanee of seeds transported by rising water during reservoir impoundment was limited due to short-floating time of the seeds and relatively low speed of water level rise in the reservoir.This would be favourable to the development of intraspecific differentiation in seed flooding tolerance.