Major Vegetation Research Articles

Impact of Vegetation on Lateral Exchanges in a Salt Marsh‐Tidal Creek System

AbstractSalt marshes are ecologically and physically essential habitats in coastal intertidal flats. In addition to providing nursery grounds for various wildlife, vegetation in marshes acts as a buffer zone that slows flooding waters. Extensive marsh platforms can also attenuate wave energy to protect coastal communities. Complex geometries make it challenging for models to capture the spatiotemporal variabilities in the transport of lateral water and sediment over tidal creek‐marsh complexes. To study water exchange processes between tidal creeks and marshes, field observations were conducted within tidal creeks in the Chongming Dongtan Shoal of the Changjiang Estuary, an area dominated by Phragmites australis, Scirpus mariqueter, and Spartina alterniflora. A coupled wave‐current‐sediment‐vegetation model that parameterized the three vegetation species was developed and applied to the tidal creek complex of Chongming Dongtan. Validated with the observational data, the modeling results were used to examine the influence of vegetation on flooding/draining processes within tidal creeks and mudflats. The model showed that vegetation not only modified the flow pattern at high tide in the high‐elevation marsh but also significantly intensified the tidal flows in tidal creeks in the low‐elevation regions. Both the observations and model detected significant transport of water and sediment from the marsh to tidal creeks, seaward sediment export over tidal cycles. The simulated salinity exhibited a considerable spatial gradient, matching well with the salt tolerances of the major vegetation types. This model can be potentially used to determine how future scenarios of hydrodynamics could affect vegetation zonation.

Scenarios of potential vegetation distribution in the different gradient zones of Qinghai-Tibet Plateau under future climate change

The spatial distribution of potential vegetation types in Qinghai-Tibet Plateau presents a significant vertical zonation. Explicating the vertical differences of potential vegetation distribution under future climate change in Qinghai-Tibet Plateau is an important issue for understanding the response of terrestrial ecosystem to climate change. Based on the observed climate data in 1981–2010 (T0), the scenario data of RCP 2.6, RCP 4.5 and RCP 8.5 released by CMIP5 in 2011–2040 (T1), 2041–2070 (T2) and 2071–2100 (T3), and the digital elevation model (DEM) data, the Holdridge life zone (HLZ) model has been improved to simulate the scenarios of potential vegetation distribution in the different gradient zones of Qinghai-Tibet plateau. The shift model of mean center has been improved to calculate the shift direction and distance of mean center in the potential vegetation types. The ecological diversity index was introduced to compute the ecological diversity change of potential vegetation. The simulated results show that there are 17 potential vegetation types in Qinghai-Tibet Plateau. Wet tundra, high-cold moist forest and nival are the major potential vegetation types and cover 56.26% of the total area of Qinghai-Tibet Plateau. Under the three scenarios, the nival would have the largest decreased area that would be decreased by 3.340 × 104 km2 per decade, and the high-cold wet forest would have the greatest increased area that would be increased by 3.340 × 104 km2 on average per decade from T0 to T3. The potential vegetation types distributed in the alpine zone would show the fastest change ratio (11.32% per decade) and that in low mountain and other zone would show the slowest change ratio (7.54% per decade) on average. The ecological diversity and patch connectivity of potential vegetation would be decreased by 0.108% and 0.290% per decade on average from T0 to T3. In general, the potential vegetation types distributed in the high elevation area generally have a higher sensitivity to climate change in Qinghai-Tibet plateau in the future.

AN ECONOMIC ANALYSIS OF PRODUCTION AND MARKETING OF MAJOR VEGETABLES IN PARSA DISTRICT, NEPAL

The survey research was conducted to analyze the economics of production and marketing of major vegetables in Parsa district of Nepal from December 2019 to April 2020. Primary data for the household survey were collected using a semi-structured questionnaire from sixty sampled respondents, sixteen from Pokhariya municipality, and forty-four from Bahudarmai municipality. Secondary data were collected through scientific journals, articles, and publications from agricultural organizations, projects, and programs. Average area under vegetable cultivation was found 12.68 Kattha. Out of five major vegetables under study average cost of production per kattha was found highest for pointed gourd (Rs. 11551.50) lowest for okra production (Rs. 6071/kata). The majority of production cost was covered by labor cost (>40%). The average productivity of cauliflower, okra,brinjal, chilli, and pointed gourd was 27.3 Mt/ha,19 Mt/ha,16.67 Mt/ha, 27.52Mt/ha, and 25.83Mt/ha respectively. B:C ratio of all the vegetables under study was higher than three which implies that vegetable farming in the study area is profitable farm business. Producers-wholesalers-retailers-consumers was the most used marketing channel. Market margin of cauliflower, okra, brinjal, chilli and pointed gourd was Rs. 13/kg, Rs. 7.73/kg, Rs. 7.86/kg, Rs. 28.07/kg and Rs. 8.69/kg respectively. Index of severity was constructed to rank the problems in the production and marketing of vegetables. Analysis of the problems identified shows the need for proper storage facilities, training related to vegetable farming and insect pest management, and subsidies on regular basis, and mechanization and modernization of the farming system through the introduction of technological knowledge and modern farm practice.

PENYULUHAN TENTANG PENCEGAHAN KEJADIAN KECACINGAN PADA ANAK DI DESA PENEN KECAMATAN BIRU-BIRU

From the results of the study, it turns out that the prevalence of worm disease is still high, namely 60-70%. This parasite is found all over the world. The frequency of this worm disease in Jakarta is quite high. In Bekasi, 1083 school children show a frequency of 24.4%. The incidence rate in Indonesia is still very high, namely almost all children aged 1-10 years have Ascariasis infection, while in adults it is estimated that 60% (in Jakarta).
 Indonesia still thrives on worm disease, the reason is that the personal hygiene of the community is still lacking. There are still many people who defecate on the ground, in rivers, in ditches, and on rice fields. Worm eggs can also be attached to major vegetables, that is, if the major vegetables are not cleaned using ditch water, river water and water that has been contaminated by worm eggs. Various factors that support the high rate of stomach infection pain in Indonesia are Indonesia's geographical location in the tropics which has a hot but humid climate, which allows stomach worms to breed well.

Documentation of Vascular Plants of Mudumalai Tiger Reserve, Western Ghats, India

The wide range of climatic factors and their interaction reflect the diversity of the vegetation communities. The major vegetation types of Mudumalai Tiger Reserve (MTR) includes Southern Tropical dry thorn forest, Southern Tropical dry deciduous forest, Southern Tropical moist deciduous forest, Southern Tropical semi-evergreen, moist bamboo brakes and Riparian fringing forest. A total of 426 plant species under 311 genera belong to 100 families, including infraspecific taxa were recorded from the study area. Fabaceae is the dominant family with represents 42 species; similarly Ficus is the dominant genera with 9 species have been recorded. The MTR is a home for many rare and threatened plants. The present study we recorded 81 plants are under threatened condition. Using vegetation data collected from the larger Nilgiri Biosphere Reserve, in and around the five tribal settlements in Mudumalai Tiger Reserve. The current study concluded that the MTR poses a severe and persistent conservation threat to both within and outside protected reserve forests.

Fire in Semi-Arid Shrublands and Woodlands: Spatial and Temporal Patterns in an Australian Landscape

Semi-arid landscapes are of interest to fire ecologists because they are generally located in the climatic transition zone between arid lands (where fires tend to be rare due to lack of fuel, but are enhanced following large rainfall episodes) and more mesic regions (where fire activity tends to be enhanced following severe rainfall deficits). Here we report on the characteristics of the contemporary fire regimes operating in a semi-arid region of inland south-western Australia with rainfall averaging around 300 mm per annum. To characterize fire regimes, we analyzed a geodatabase of fire scars (1960–2018) to derive fire preferences for each major vegetation type and fire episode and used known fire intervals to model fire hazard over time and calculate typical fire frequencies. We also used super epoch analysis and correlations to explore relationships between annual fire extent and rainfall received before the fire. We found fires strongly favored sandplain shrublands, and these tended to experience hot crown fires once every 100 years (median fire interval), with fire hazard increasing linearly over time. In contrast, fires were rare in eucalypt woodland and other vegetation types, with a median interval of 870 years and broadly consistent fire hazard over time. Annual fire extent was most strongly linked with high rainfall in the year prior to fire, and this was particularly so for eucalypt woodlands. Large-scale fires in shrublands tended to favor areas burnt in previous large fires, whereas in woodlands they favored edges. In conclusion, we found divergent fire regimes across the major vegetation types of the region. Sandplain shrublands were similar to Mediterranean shrublands in that they experienced intense stand-replacing wildfires which recovered vigorously although slowly, meaning burnt shrublands did not experience fires again for at least 25 and 100 years on average. In contrast, eucalypt woodlands were fire sensitive (trees readily killed by fire) and experienced fires mostly around the edges, spreading into core areas only after large rainfall events elevated fuel levels. Overall, both vegetation types subscribed to typical arid-zone fire regimes where elevated rainfall, and not drought, promoted fires, although the role of fuel accumulation over time was more important in the shrublands.

Food prices and marketing margins during the COVID-19 pandemic: Evidence from vegetable value chains in Ethiopia.

It is widely feared that the shock of the COVID‐19 pandemic will lead to a significant worsening of the food security situation in low and middle‐income countries. One reason for this is the disruption of food marketing systems and subsequent changes in farm and consumer prices. Based on primary data in Ethiopia collected just before the start and a few months into the pandemic, we assess changes in farm and consumer prices of four major vegetables and the contribution of different segments of the rural‐urban value chain in urban retail price formation. We find large, but heterogeneous, price changes for different vegetables with relatively larger changes seen at the farm level, compared to the consumer level, leading to winners and losers among local vegetable farmers due to pandemic‐related trade disruptions. We further note that despite substantial hurdles in domestic trade reported by most value chain agents, increases in marketing—and especially transportation—costs have not been the major contributor to overall changes in retail prices. Marketing margins even declined for half of the vegetables studied. The relatively small changes in marketing margins overall indicate the resilience of these domestic value chains during the pandemic in Ethiopia.

The potential role of an alien tree species in supporting forest restoration: Lessons from Shiretoko National Park, Japan

Restoring forests has recently received considerable attention in the context of sequestering carbon and supporting biodiversity. Although considering alien species as a tool for natural forest restoration still remains controversial, harnessing alien species when they are already present in an ecosystem might result in overall benefits for nature and society. In this study we evaluated whether the presence of an alien tree species supports or hinders the establishment of naturally regenerating forests in Shiretoko National Park, Japan. In particular, we focused on Larix kaempferi, which is widely present yet non-native to the region, and examined how this alien species affects two factors influencing the success of restoration: wind disturbance and deer herbivory. We examined the following effects of L. kaempferi plantations on natural regeneration: (1) the windbreak function for protecting native tree growth and (2) the nursery function to promote the regeneration of native tree saplings and seedlings under high herbivory pressure. We assessed tree height and regeneration, using large-scale remotely sensed data and terrestrial inventory data in five major vegetation types. We found that L. kaempferi plantations can protect native species from predominant winds. Additionally, L. kaempferi canopy cover promoted abundance and species richness in understory saplings and seedlings compared to other vegetation types such as primary and secondary forests, even under excessive browsing pressure. No regenerating L. kaempferi individuals were observed during the field census, suggesting the species is likely not invasive in our study system. The positive relationship between alien tree species and the regeneration of native tree assemblages emphasizes that existing alien species have the potential to act as nurse plants. Our findings imply that the presence of alien species can contribute to natural forest restoration by improving the local environmental conditions for native species in the short-term. Given the multiple ecological and social needs in our changing world, careful consideration is required to evaluate the long-term consequences of alien species. Especially in ecosystems in which alien species have already established, using their positive functions rather than swiftly eradicating them from the landscape might be beneficial for long-term restoration goals. We conclude that managers need to be aware of the context-dependency of alien species to make restoration more effective.

Smallholder farmers’ perception on tomato (solanum lycopersicum) seedling technologies in the north west zone of Nigeria

The research was funded by Syngenta Foundation for sustainable Agriculture, Nigeria to ascertain Farmer’s perception on tomato seedlings technology in North West Zone of Nigeria. Multistage sampling technique was employed for the selection of One hundred and ninety-five (195) producers of Tomato in Kano and Jigawa States. Data were collected with the aid of a questionnaire. Data obtained were analysed using mean, standard deviation, coefficient of variation, charts, and graphs. The results of the study revealed that the producers of tomato had a mean age of 38 years, majorly males (86%) with secondary school education (32%), married (88%) with mean household size of 11 persons, mean farming experience, vegetable experience and tomato production experience of 18, 13 and 12 years respectively, mean land cultivated 3ha and mean tomato farm size of 2ha. Maize, sorghum, and rice are the three most cultivated crops by the farmers with tomato and onions as major vegetables. Plum tomato (UTC) variety (34%) is the most widely cultivated during both dry and wet seasons. The study further revealed that 82% of the farmers used recycled seeds to produce seedlings, 88% of the farmers had no extension and advisory service training, 59% made use of seedlings for planting with Plum tomato (UTC) as the common variety, 95% are interested in buying and selling seedlings, and 98% propagated their seeds in the open field. Therefore, it is recommended from the study that public and private’s sector at all levels should strengthen extension service systems to increase farmers’ knowledge and understanding of new tomato production technology-through provision of tomato seedlings technology, frequent trainings and marketing demos establishment to showcase this new innovation, Seed companies should ensure that seed packages contain recommended agronomic practices for all round effectiveness.

Beyond trees: Mapping total aboveground biomass density in the Brazilian savanna using high-density UAV-lidar data

Tropical savanna ecosystems play a major role in the seasonality of the global carbon cycle. However, their ability to store and sequester carbon is uncertain due to combined and intermingling effects of anthropogenic activities and climate change, which impact wildfire regimes and vegetation dynamics. Accurate measurements of tropical savanna vegetation aboveground biomass (AGB) over broad spatial scales are crucial to achieve effective carbon emission mitigation strategies. UAV-lidar is a new remote sensing technology that can enable rapid 3-D mapping of structure and related AGB in tropical savanna ecosystems. This study aimed to assess the capability of high-density UAV-lidar to estimate and map total (tree, shrubs, and surface layers) aboveground biomass density (AGBt) in the Brazilian Savanna (Cerrado). Five ordinary least square regression models estimating AGBt were adjusted using 50 field sample plots (30 m × 30 m). The best model was selected under Akaike Information Criterion, adjusted coefficient of determination (adj.R2), absolute and relative root mean square error (RMSE), and used to map AGBt from UAV-lidar data collected over 1,854 ha spanning the three major vegetation formations (forest, savanna, and grassland) in Cerrado. The model using vegetation height and cover was the most effective, with an overall model adj-R2 of 0.79 and a leave-one-out cross-validated RMSE of 19.11 Mg/ha (33.40%). The uncertainty and errors of our estimations were assessed for each vegetation formation separately, resulting in RMSEs of 27.08 Mg/ha (25.99%) for forests, 17.76 Mg/ha (43.96%) for savannas, and 7.72 Mg/ha (44.92%) for grasslands. These results prove the feasibility and potential of the UAV-lidar technology in Cerrado but also emphasize the need for further developing the estimation of biomass in grasslands, of high importance in the characterization of the global carbon balance and for supporting integrated fire management activities in tropical savanna ecosystems. Our results serve as a benchmark for future studies aiming to generate accurate biomass maps and provide baseline data for efficient management of fire and predicted climate change impacts on tropical savanna ecosystems.

POTENTIAL IN BIOETHANOL PRODUCTION FROM VARIOUS AGRO WASTES FERMENTING BY MICROORGANISMS USING CARROT PEEL, ONION PEEL, POTATO PEEL AND SUGAR BEET PEEL AS SUBSTRATES.

Large amount of agro wastes are produced in Rwanda each year. The global annual potential bioethanol production from the major vegetables wastes such as carrot peel, onion peel, potato peel and sugar beet peel was estimated. Those wastes processing were successfully used as raw materials for the production of bioethanol, employing by cellulase produced from various filamentous fungi including Cladosporium cladosporioides was used for hydrolysis and the fermentation of the hydrolyzed samples was done using Sacharomyces cerevisiae. The fermented product was purified by primary distillation process at 79 °C and the fraction was collected. The ethanol is then determined by specific dichromate method and Gas Chromatography. Instantaneous saccharification and fermentation process yielded maximum ethanol in the substrate of carrot peel was 16.9 % at 21st day and further confirmed by Gas chromatography and the yield of ethanol obtained was 15.8 %.

Time‐series of δ26Mg values in a headwater catchment reveal decreasing magnesium isotope variability from precipitation to runoff

AbstractData on temporal variability in Mg isotope ratios of atmospheric deposition and runoff are critical for decreasing the uncertainty associated with construction of isotope mass balances in headwater catchments, and statistical evaluation of isotope differences among Mg pools and fluxes. Such evaluations, in turn, are needed to distinguish between biotic and abiotic contributions to Mg2+ in catchment runoff. We report the first annual time‐series of δ26Mg values simultaneously determined for rainfall, canopy throughfall, soil water and runoff. The studied 55‐ha catchment, situated in western Czech Republic, is underlain by Mg‐rich amphibolite and covered by mature spruce stands. Between 1970 and 1996, the site received extremely high amounts of acid deposition and fly ash form nearby coal‐burning power plants. The δ26Mg values of open‐area precipitation (median of −0.79‰) at our study site were statistically indistinguishable from the δ26Mg values of throughfall (−0.73‰), but significantly different from the δ26Mg values of soil water (−0.55‰) and runoff (−0.55‰). The range of δ26Mg values during the observation period decreased in the order: open‐area precipitation (0.57‰) > throughfall (0.27‰) > runoff (0.21‰) > soil water (0.16‰). The decreasing variability in δ26Mg values of Mg2+ from precipitation to soil water and runoff reflected an increasing homogenization of atmospheric Mg in the catchment and its mixing with geogenic Mg. In addition to atmospheric Mg, runoff also contained Mg mobilized from the three major solid Mg pools, bedrock (δ26Mg of −0.32‰), soil (−0.28‰), and vegetation (−0.31‰). The drought of summer 2019 did not affect the nearly constant δ26Mg value of runoff. Collectively, our data show that within‐catchment processes buffer the Mg isotope variability of the atmospheric input.

Phylogenetic structure of lichen metacommunities in Amazonian and Northeast Brazil

AbstractAmazon, Atlantic forest, Brejos de Altitude, Caatinga, Carrasco, Cerradão and Restinga are major vegetation units in North and Northeast Brazil. Little is known about lichen metacommunity structure in these habitats. While species richness and composition generally depend on climatic factors, in azonal vegetation edaphic factors may have a filtering effect on tree bark structure and hence the composition of epiphytic lichen communities. We hypothesized that climatic stress and a tree bark filtering effect would result in reduced richness and phylogenetic clustering in Caatinga, Carrasco, Cerradão and Restinga, whereas high richness and phylogenetic overdispersion were predicted for Amazon and Atlantic Forest. To test this, we analyzed 2,090 lichenized species in the study area, with a supertree to assess phylogenetic metacommunity structure. Amazon and Atlantic forest exhibited high richness and phylogenetic diversity, with phylogenetic overdispersion only in the Amazon. The zonal Caatinga with drought stress and the extrazonal Brejos both exhibited phylogenetic clustering. Among the azonal, edaphic vegetation units, Cerradão exhibited phylogenetic overdispersion, whereas Restinga showed phylogenetic clustering. Nearest taxon phylogenetic distance indicated a close relationship between Amazon and Atlantic forest, Atlantic forest and Brejos and Atlantic forest and Caatinga. Carrasco was mostly closely related to Cerradão, and Restinga was distantly related to any other unit. These findings indicate more complex patterns in the phylogenetic structure of lichen metacommunities, partly reflecting those of plant metacommunities, as a result of concurrent macroecological evolutionary histories. Our data supported floristic evidence that Carrasco is part of the Cerrado complex and not related to Caatinga.

Dynamics of Soil Nutrients, Microbial Community Structure, Enzymatic Activity, and Their Relationships along a Chronosequence of Pinus massoniana Plantations

Pinus massoniana is the major afforestation and vegetation restoration tree in southern China, and it plays an important role in the sustainable development of plantations. However, long-term single planting of P. massoniana has resulted in the decline of soil quality and forest productivity, and a soil fertility assessment is urgently needed. We selected P. massoniana plantations of four age stages for plot investigation and sampling to determine the soil physicochemical properties, microbial diversity and composition, and enzyme activities at different soil depths. The results showed that soil total phosphorus (TP) and available phosphorus (AP) decreased with the increase of age, especially low C/N ratio and high C/P and N/P ratio in the 30-year and 36-year stands, leading to P limitation. Meanwhile, the bacterial Shannon index also decreased with the increase of age and was positively correlated with AP, NO3−-N, and pH. However, the fungal Shannon index decreased first and then increased with the increase of age; soil acid phosphatase (S-ACP) and urease activities showed a similar trend. Correlation analysis demonstrated that the increase of total organic carbon (TOC) and total nitrogen (TN) promoted the increase of fungal Shannon index, which was beneficial to the secretion of more enzymes. We found that soil physicochemical properties, microbial diversity, and enzyme activity decreased simultaneously when soil depths increased. Moreover, Acidobacteria and Basidiomycota were the most abundant bacterial and fungal communities, respectively, followed by Proteobacteria and Actinobacteria for bacteria and Ascomycota for fungi, and these microbial taxa were significantly affected by soil water content (SWC), TOC, AP, and C/P. In conclusion, this work reveals the potential correlation among soil physicochemical properties, microbial diversity and composition, and enzyme activities, and revealed potential correlations among them which will help to improve understanding of soil conditions and provide a reference for rational management of soil resources.

Dissipation kinetics and dietary risk assessment of spiromesifen on major summer vegetables using good agricultural practices.

Dissipation kinetics and dietary risk assessment of spiromesifen is worked out on four summer vegetables, viz. okra, chilli, capsicum and brinjal (eggplant or aubergine) during March-April 2015 at the experimental farm of the Department of Entomology, Dr. Yashwant Singh Parmar University of Horticulture and Forestry Nauni, Solan using good agricultutral practices. Two foliar applications of spiromesifen @ 144.0g.a.i./ha each were given at 10days interval with a knapsack sprayer with the first application at the fruit initiation stage. Sample were collected up to 15 days after pesticide application and processed using a modified QuEChERS method, which was validated by doing recovery studies having recovery range and RSD within established guidelines of SANCO. Estimation of spiromesifen residues was conducted on GC-MS. The initial deposits after spraying of spiromesifen on okra, capsicum, chilli and brinjal fruit after 2h of treatment were 1.327, 0.727, 0.800 and 0.738 mg/kg, respectively. The residues persisted up to 7days and further dissipated and declined below the limit of quantification of <0.025 mg/kg at 10days after treatment in all of the crops under investigation. Dissipation of spiromesifen followed first-order kinetics. The spiromesifen residues dissipated to half in 1.6, 1.8, 1.9 and 1.7days with the suggested safe waiting period of 8.9, 5.2, 6.0 and 7.0 in the respective crops. The hazard quotient was <1 and theoretical maximum dietary intake was less than the maximum permissible intake, which was less than the maximum residue limit in all of the vegetable crops under investigation.

Implications of the 2019\u20132020 megafires for the biogeography and conservation of Australian vegetation

Australia’s 2019–2020 ‘Black Summer’ bushfires burnt more than 8 million hectares of vegetation across the south-east of the continent, an event unprecedented in the last 200 years. Here we report the impacts of these fires on vascular plant species and communities. Using a map of the fires generated from remotely sensed hotspot data we show that, across 11 Australian bioregions, 17 major native vegetation groups were severely burnt, and up to 67–83% of globally significant rainforests and eucalypt forests and woodlands. Based on geocoded species occurrence data we estimate that >50% of known populations or ranges of 816 native vascular plant species were burnt during the fires, including more than 100 species with geographic ranges more than 500 km across. Habitat and fire response data show that most affected species are resilient to fire. However, the massive biogeographic, demographic and taxonomic breadth of impacts of the 2019–2020 fires may leave some ecosystems, particularly relictual Gondwanan rainforests, susceptible to regeneration failure and landscape-scale decline.

Improvement of cabbage growth and yield by nanofertilizers and nanoparticles

Cabbage Brassica oleracea var. capitata L. is one of major winter leafy vegetable which belong to cruciferae family. The local seedlings of 30 days’ cabbage were implanted in 100 m2 land in the Abu Ghraib region, Baghdad, at the 1st of October 2019 and harvested after 75 days, as one agriculture season in Iraq. The plants divided into 6 groups, each includes 45 plants. One of the six groups do not receive any type of fertilizers, as control, while the last 5 groups received different types of nanofertilizers every 21 days. CeO2 prepared by laser ablation and commercial iron and zinc nanoparticles were characterized by field emission scanning electron microscope (FE-SEM), x-ray diffraction (XRD) and energy dispersive x–ray (EXD). The three metal nanoparticles were used as microelements to enhance NPK nanofertilizer. Cabbages that fertilized with nanofertilizers revealed higher circumferences (not less 49.42 cm) when compared with control (28.17 cm). High average of head circumference (56.22 cm) was observed when plant fertilized with NPK + Fe nano fertilizer. On the other hand, cabbages that did not receive any nano fertilizers, as control, show height head of 10.67 cm, while the height head average of 16.67 cm was observed when plant fertilized with NPK + Fe nano fertilizer. Moreover, the higher average of cabbage head weight increased three times more than than control to reach 1.88 Kg/plant when the cabbage fertilized with NPK + CeO2 NPs within 75 days. Furthermore, the higher chlorophyll content of 131.22 mg / 100 g plant leaves was observed in cabbage that fertilized with NPK + CeO2 NPs. Significant differences were obtained between the higher values and others.

Afforestation suppresses Oncomelania hupensis snail density through influencing algae in beaches of the Dongting Lake.

BackgroundOncomelania snails serve as the sole intermediate host for Schistosoma japonicum, one of the most important neglected tropical diseases in the world. Afforestation suppression of the Oncomelania hupensis snail has been a long-term effective national strategy to decrease snail density in China. Many previous studies have made clear that vegetation (biotic factors) and soil (abiotic factors) were the basic requirements for snail survival on beaches. Moreover, a lot of research on snail control has been focused on the specific influencing environmental factors for snail survival, such as the vegetation community structure, species composition, diversity index, and the physical and chemical properties of the soil. Most of the existing research has studied the influence of a single factor on snail population density. Conversely, there have been only a few studies focused on the food sources and food composition of the snails. The current research situation on snail control has indicated that the mechanisms underlying ecological snail control have not been systematically characterized. The question of whether biotic or abiotic factors were more important in influencing snail survival remains unclear. Afforestation on beaches has significantly suppressed snail density in China so far. In this study, we proposed that the reduction of snail density was not affected by a single factor but by the interactions of multiple related factors introduced by afforestation. Moreover, different biotic and abiotic factors have significantly different effects on snail control. Therefore the goal of this study was to evaluate the relative importance and interactions of related biotic and abiotic factors on snail density. Methods: Four major vegetation communities: Sedge, Reed, Artificial poplar (3 years of age) and Artificial poplar (5 years of age), on the beaches of the Yangtze River in China were selected for vegetation and snail surveys, as well as for soil sampling. Structural Equation Model (SEM) analysis was used to assess the interactions of biotic and abiotic factors in the context of snail ecology. The soil properties were considered as abiotic factors, while algae of Chlorophyta, Cyanophyta and Bacillariophyta phyla were considered to be biotic factors. In the path analysis, the total effect between the variables was the sum of the direct and indirect effects.ResultsThe snail density had significant correlations with soil properties, such as water content, bulk density, capillary porosity and pH value, as well as with all three types of soil algae, Chlorophyta, Cyanophyta, and Bacillariophyta. Snail density had a direct negative relationship with capillary porosity and soil bulk density, an indirect negative relationship with soil pH value and an indirect positive relationship with soil water content via soil algae. Meanwhile, as an important food source for the snail, the Chlorophyta, Cyanophyta and Bacillariophyta algae had a significant positive correlation with snail density. High soil pH had a negative impact on Chlorophyta, Bacillariophyta, while soil water content had a positive impact on Chlorophyta, and soil bulk density had a negative impact on Cyanophyta. In addition, the soil pH value and soil bulk density both had negative correlations with soil water content.ConclusionAfforestation of the beach environment can significantly reduce the snail population density by altering ecological factors. Soil algae (biological factors) might be the key element that drives ecological snail control. As important habitat determinants, the impact of the properties of the soil (non-biological factors) on the snail population was largely mediated through soil algae.

Assessing multi-temporal changes of natural vegetation cover between 1987-2018 using serial NDVI: A case study of Tlemcen national park (north-west of Algeria)

ABSTRACT Landscape spatial metrics were investigated to assess changes of multi-temporal vegetation cover within the Tlemcen national park (TNP) in north-western Algeria over 31 years. Five landscape metrics, namely number of patches (NP), landscape shape index (LSI), class area (CA), largest patch index (LPI), and percentage of landscape (PLAND) were applied and analysed to assess the fragmentation in the TNP at landscape and class levels. Three Landsat images acquired at three periods of time (1987, 1999 and 2018) with different sensors, namely Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+) and Operational Land Imager (OLI) were used. After rigorous pre-processing steps, these images were transformed and thresholded into Normalised Difference Vegetation Index (NDVI) maps that represent the major vegetation cover classes in TNP. The obtained results revealed that during the study period the TNP has undergone a progressive and significant landscape fragmentation.

An Estimation of the Acreage Response Function of Major Vegetables in Gyeongnam Province

An Estimation of the Acreage Response Function of Major Vegetables in Gyeongnam Province