Unveiling the adaptation strategies of woody plants in remnant forest patches to spatiotemporal urban expansion through leaf trait networks

Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion on the networks of leaf traits in woody plants within remnant forest patches,thereby enhancing our understanding of plant adaptive strategies and contributing to the conservation of urban biodiversity.Methods:Our study examined woody plants within 120 sample plots across 15 remnant forest patches in Guiyang,China.We constructed leaf trait networks (LTNs) based on 26 anatomical,structural,and compositional leaf traits and assessed the effects of the spatiotemporal dynamics of urban expansion on these LTNs.Results and conclusions:Our results indicate that shrubs within these patches have greater average path lengths and diameters than trees.With increasing urban expansion intensity,we observed a rise in the edge density of the LTN-shrubs.Additionally,modularity within the networks of shrubs decreased as road density and urban expansion intensity increased,and increases in the average path length and average clustering coefficient for shrubs were observed with a rise in the composite terrain complexity index.Notably,patches subjected to‘leapfrog’expansion exhibited greater average patch length and diameter than those experiencing edge growth.Stomatal traits were found to have high degree centrality within these networks,signifying their substantial contribution to multiple functions.In urban remnant forests,shrubs bolster their resilience to variable environmental pressures by augmenting the complexity of their leaf trait networks.

Organic Acids Secreted from Plant Roots under Soil Stress and Their Effects on Ecological Adaptability of Plants

[Objective] In this study,the secretion of organic acids from plant roots under soil nutrient and water stress and the effects of organic acids on ecological adaptability of plants were investigated,which provided theoretical basis for improving the adaptability of plants to a variety of stress conditions.The results showed that,under nutrient and water stress,the content of organic acids secreted from plant roots increased significantly as a common active adaptive response.Organic acids could improve the activities of a variety of antioxidant enzymes,contents of osmotic regulatory substances,contents of chlorophyll and photosynthesis levels,promote nutrient absorption and transportation in plants,and ultimately contribute to plant growth and biomass accumulation,reduce the toxicity of stress conditions to plants and improve the stress resistance and adaptability of plants.

Changes in leaf vein traits among vein types of alpine grassland plants on the Tibetan Plateau

Vein traits influence photosynthesis and drought resistance and are sensitive to climate change.It is unclear whether vein traits,similar to other leaf traits,have obvious regional characteristics and covariance with other leaf traits,especially in Tibetan Plateau grasslands.We collected 66 species from 37 sites in late July of 2012 and early August of 2013 to investigate leaf vein traits and their relationships with other leaf traits in comparison with the available global database data and to elucidate vein investment of plants with different vein types.The average vein length per area(VLA)of plants in the Tibetan Plateau was within the range of the global dataset,and the relationships among vein traits and other leaf traits of alpine plants were consistent with the global models.The VLAs of parallel-veined grasses and pinnateveined forbs were significantly lower and higher than the global mean value,respectively.The leaf mass perarea and total nitrogen content of parallel-veined grasses were significantly lower and higher,respectively,than the global mean values;the opposite was observed in pinnate-veined forbs.The parallel-veined grasses exhibited almost a four-fold higher vein biomass investment(i.e.,vein mass per leaf mass)than pinnate-veined forbs in the same region.The average VLA and its relationships with other leaf traits of the alpine grassland plants on the Tibetan Plateau had no regional characteristics,suggesting a convergence in plant leaf functioning.Plants with different leaf types differ in their adaptation strategies to plateau environments,and this may relate to biomass investment into leaf veins.Our study fills the gap with regard to vein density in alpine grassland species and provides a new perspective for understanding plant physiology and ecology by calculating and comparing the proportion of vein investment among different vein types.

Three Dimensional Optimum Node Localization in Dynamic Wireless Sensor Networks

Location information plays an important role in most of the applications in Wireless Sensor Network(WSN).Recently,many localization techniques have been proposed,while most of these deals with two Dimensional applications.Whereas,in Three Dimensional applications the task is complex and there are large variations in the altitude levels.In these 3D environments,the sensors are placed in mountains for tracking and deployed in air for monitoring pollution level.For such applications,2D localization models are not reliable.Due to this,the design of 3D localization systems in WSNs faces new challenges.In this paper,in order to find unknown nodes in Three-Dimensional environment,only single anchor node is used.In the simulation-based environment,the nodes with unknown locations are moving at middle&lower layers whereas the top layer is equipped with single anchor node.A novel soft computing technique namely Adaptive Plant Propagation Algorithm(APPA)is introduced to obtain the optimized locations of these mobile nodes.Thesemobile target nodes are heterogeneous and deployed in an anisotropic environment having an Irregularity(Degree of Irregularity(DOI))value set to 0.01.The simulation results present that proposed APPAalgorithm outperforms as tested among other meta-heuristic optimization techniques in terms of localization error,computational time,and the located sensor nodes.

The Adaptive Planting and the Prospect of Industrial Development of Quinoa in China

Quinoa is the only single plant meeting the basic nutritional needs of the human body. It is the whole nutritious food with nutritional balance, wide adaptability, strong resistance and other characteristics. In this paper, the botanical characteristics and nutritional value of quinoa were systematically introduced, and the development of quinoa in China was reviewed. The problems of domestic quinoa industry, the shortage of germplasm resources, the lack of innovation and high-yielding cultivation techniques were analyzed. To provide theoretical references for quinoa planting and industrial development in China, the countermeasures to improve the investment of quinoa industry and promote the development of multi-form industry were put forward.

Native Aquatic Plant Establishment Efforts in a High-Herbivore, Central Texas Reservoir

Maintaining beneficial, native plant structure and diversity while reducing invasive, nuisance species dominance is an important management domain for natural resource managers. One such vegetation component in North American lakes and reservoirs is submerged aquatic vegetation—a valuable aquatic resource which serves as productive habitat for fish, aquatic macroinvertebrates, and other wildlife. Reservoirs in the southern parts of the United States have experienced varying aquatic plant dominance dynamics due to historical water resource management actions, including drawdowns and introduction of herbivorous fish for the purpose of controlling invasive aquatic vegetation. Some of these management options have also been detrimental to native submerged aquatic vegetation. This paper explores an adaptive management research effort by installing herbivore-protected, fenced-pen submerged aquatic vegetation sites in a high-herbivore reservoir to determine effectiveness of protecting habitat and serving as founder colony sources for propagule spread. Four experimental sites with three management treatments each were planted with American eelgrass. Each site utilized one un-fenced treatment and two treatments with varying mesh sizes for protective fencing-pens. Site integrity, species survival and spread, and grazing were documented. One additional site was installed and planted with other native submerged aquatic vegetation species for nominal species performance descriptions. No plants survived unprotected in the high-herbivore system and plants, in general, performed consistently better within the smaller mesh size. These test planting results were ultimately used to inform adaptive management decision making for plant installation and expansion designs for managing reservoirs invested with Hydrilla, considered one of the most serious invasive aquatic plants in the United States.

Cradle for the newborn Monochamus saltuarius:Microbial associates to ward off entomopathogens and disarm plant defense

The Japanese pine sawyer,Monochamus saltuarius,as a beetle vector of Bur-saphelenchus xylophilus(pine wood nematode),is an economically important forest pest in Eurasia.To feed on the phloem and xylem of conifers,M.saltuarius needs to overcome various stress factors,including coping with entomopathogenic bacteria and also various plant secondary compounds(PSCs).As an important adaptation strategy to colonize host trees,M.saltuarius deposit eggs in oviposition pits to shield their progeny.These pits har-bor bacterial communities that are involved in the host adaptation of M.saltuarius to the conifers.However,the composition,origin,and functions of these oviposition pit bacteria are rarely understood.In this study,we investigated the bacterial community associated with M.saltuarius oviposition pits and their ability to degrade PSCs.Results showed that the bacterial community structure of M.saltuarius oviposition pits significantly differed from that of uninfected phloem.Also,the oviposition pit bacteria were predicted to be enriched in PSC degradation pathways.The microbial community also harbored a lethal strain of Serratia,which was significantly inhibited.Meanwhile,metatranscriptome anal-ysis indicated that genes involved in PSCs degradation were expressed complementarily among the microbial communities of oviposition pits and secretions.In vitro degrada-tion showed that bacteria cultured from oviposition pits degraded more monoterpenes and flavonoids than bacteria cultured from uninfected phloem isolates.Disinfection of ovipo-sition pits increased the mortality of newly hatched larvae and resulted in a significant decrease in body weight in the early stages.Overall,our results reveal that M.saltuarius construct oviposition pits that harbor a diverse microbial community,with stronger PSCs degradation abilities and a low abundance of entomopathogenic bacteria,resulting in the increased fitness of newly hatched larvae.

Role of digestive protease enzymes and related genes in host plant adaptation of a polyphagous pest,Spodoptera frugiperda

The evolutionary success of phytophagous insects depends on their ability toefficiently exploit plants as a source of energy for survival.Herbivorous insects largelydepend on the efficiency,flexibility,and diversity of their digestive physiology and sophistication of their detoxification system to use chemically diverse host plants as foodsources.The fall armyworm,Spodoptera frugiperda(J.E.Smith),is a polyphagous pest ofmany commercially important crops.To elucidate the ability of this insect pest to adaptto host plant mechanisms,we evaluated the impact of primary(corn)and alternate(rice)host plants after 1l generations on gut digestive enzymatic activity and expression profiles of related genes.Results indicated that the total protease and classspecific trypsinand chymotrypsinlike protease activity of S.frugiperda significantly differed among hostplant treatments.The classspecifiq protease profiles greatly differed in S.frugiperdamidguts upon larval exposure to different treatments with inhibitors compared with treatments without inhibitors.Similarly,the single and cumulative effects of the enzymespecific inhibitors TLCK,TPCK,and E64 significantly increased larval mortality and reduced larval growth/mass across different plant treatments.Furthermore,the quantitativereverse transcription polymerase chain reaction results revealed increased transcription oftwo trypsin(SfTry3,SfTry7)and one chymotrypsin gene(Sfchym9),which indicatedthat they have roles in host plant adaptation.Knockdown of these genes resulted in significantly reduced mRNA expression levels of the trypsin genes.This was related to theincreased mortality observed in treatments compared with the dsRED control.This resultindicates possible roles of S.frugiperda gut digestive enzymes and related genes in hostplant adaptation.

A comprehensive framework for seasonal controls of leaf abscission and productivity in evergreen broadleaved tropical and subtropical forests

Relationships among productivity,leaf phenology,and seasonal variation in moisture and light availability are poorly understood for evergreen broadleaved tropical/subtropical forests,which contribute 25% of terrestrial productivity.On the one hand,as moisture availability declines,trees shed leaves to reduce transpiration and the risk of hydraulic failure.On the other hand,increases in light availability promote the replacement of senescent leaves to increase productivity.Here,we provide a comprehensive framework that relates the seasonality of climate,leaf abscission,and leaf productivity across the evergreen broadleaved tropical/subtropical forest biome.The seasonal correlation between rainfall and light availability varies from strongly negative to strongly positive across the tropics and maps onto the seasonal correlation between litterfall mass and productivity for 68 forests.Where rainfall and light covary positively,litterfall and productivity also covary positively and are always greater in the wetter sunnier season.Where rainfall and light covary negatively,litterfall and productivity are always greater in the drier and sunnier season if moisture supplies remain adequate;otherwise productivity is smaller in the drier sunnier season.This framework will improve the representation of tropical/subtropical forests in Earth system models and suggests how phenology and productivity will change as climate change alters the seasonality of cloud cover and rainfall across tropical/subtropical forests.

New insights into plant nutrient signaling and adaptation to fluctuating environments

Over the past 50 years, the Green Revolution and exploitation of heterosis have allowed cereal grain yield to keep pace with world- wide population growth. Unfortunately, plant growth and crop productivity are heavily dependent on the application of synthetic fertilizers.