Cultivated Sites Research Articles

Mitigation of Greenhouse Gas Emissions by Optimizing Groundwater Level in Boreal Cultivated Peatland

Optimizing the level of groundwater presents a viable strategy for mitigating the greenhouse gas (GHG) emissions associated with the cultivation of peatlands. This study investigated the impact of soil hydrological conditions on carbon dioxide (CO2) and methane (CH4) emissions. The CO2 and CH4 emissions from bare soil were continuously measured using an automated chamber system throughout the growing seasons from 2021 to 2023 at a boreal cultivated peat soil site. Annual CO2 emissions from soil respiration averaged to 21,600 kg ha-1 (April-November) corresponding to carbon (C) loss of 5890 kg ha-1. The CO2 emissions were highly temperature dependent. Lowering the groundwater level (GWL) was found to increase the CO2 emissions nearly linearly. The soil functioned as a CH4 sink for the majority of the growing season, and the total sink corresponded to 27 and 20 kg ha-1 yr-1 CO2 equivalent in 2022 and 2023, respectively. The CH4 emissions occurred generally when soil water content (SWC) exceeded 0.6 m3 m-3 and when GWL was at the depth of less than 30 cm from soil surface. For optimal climate efficiency the mitigation measures must be implemented during the mid-growing season, and the water table should be brought close to the soil surface. Potentially, this can hamper the operation of machinery on the field and reduce the harvested yield. Thus, comprehensive cost-benefit analysis is necessary before adopting a raised water table level in large-scale crop production.

Serial cascaded deep feature extraction-based adaptive attention dilated model for crop recommendation framework

Effective crop farming depends on wise selection of crops. It is an essential factor that has to be fulfilled before beginning an agricultural endeavor. Conventionally, the crop that has to be grown is selected without considering the location and cultivated site’s characteristics by only considering its profit and demand on the market. Choosing the best crop for the circumstances can minimize the need for additional fertilizer and water for irrigation and help in attaining enhanced crop yield. Therefore, choosing the right crop is crucial for a successful agricultural situation. Thus, a novel crop recommendation model by considering the soil and geographical conditions is developed to aid the farmers in choosing the appropriate crop for the right condition so that the overall production can be enhanced to increase the overall profit and decrease the losses faced by the farmers. At first, a certain geographical area is selected, and the ideal parameters for growing a particular plant are gathered from the standard database. Next, the deep optimal features are extracted using a Serial Cascaded network in which an autoencoder is cascaded with a “Dimensional Convolutional Neural Network (1DCNN)” from the gathered data. The obtained deep features are optimally selected using the developed Modified Movement Territory of Fire Hawk Optimizer (MMTFHO). These optimally selected features are given to the Adaptive and Attention-based Hybrid Network (AAHNet) in which “Gated Recurrent Unit (GRU), and Long Short Term Memory (LSTM)” are utilized for choosing the right crop for the provided geographical condition. The parameters in the AAHNet are optimized using the same enhanced MMTFHO algorithm for improving the precision of the appropriate crop selection process. The final prediction of crops for the given geographical condition is obtained from the AAHNet. The final or overall rating of the recommended approach regarding accuracy metrics is 96.73%.

Alternative host shapes transmission and life-history trait correlations in a multi-host plant pathogen.

Most pathogens are generalists capable of infecting multiple host species or strains. Trade-offs in performance among different hosts are expected to limit the evolution of generalism. Despite the commonness of generalism, the variation in infectivity, transmission, and trade-offs in performance among host species have rarely been studied in the wild. To understand the ecological and evolutionary drivers of multi-host pathogen infectivity and transmission potential, I studied disease severity, transmission dynamics, and infectivity variation of downy mildew pathogen Peronospora sparsa on its three host plants Rubus arcticus, R. chamaemorus, and R. saxatilis. In a survey of 20 wild and cultivated sites of the three host species, disease severity varied by host species and by host population size but not among wild and cultivated sites. To understand how alternative host presence and plant diversity affect transmission of the pathogen, I conducted a transmission experiment. In this experiment, alternative host abundance and plant diversity together modified P. sparsa transmission to trap plants. To understand how resistance to P. sparsa varies among host species and genotypes, I conducted an inoculation experiment using 10 P. sparsa strains from different locations and 20 genotypes of the three host species. Significant variation in infectivity was found among host genotypes but not among host species. When trade-offs for infectivity were tested, high infectivity in one host species correlated with high infectivity in another host species. However, when pathogen transmission-related life-history correlations were tested, a positive correlation was found in R. arcticus but not in R. saxatilis. The results suggest that host resistance may shape pathogen life-history evolution with epidemiological consequences in a multi-host pathogen.

Effect of agricultural activity on diet in an assemblage of lizards from Monte, Argentina

AbstractEven though the encroachment of agriculture is the main cause for biodiversity loss, studies have focused in tropical and temperate environment, mainly in birds, mammals and beneficial and/or pests' invertebrates. However, little is known about the impact in poor environment or lizards communities. Our aim was to compare food use and availability in trophic resources in two assemblages of seven lizard (Liolaemus darwinii, L. riojanus, L. cuyanus, L. wiegmannii, Aurivela longicauda, Homonota underwoodi and Teius teyou) at a cultivated and a non‐cultivated site in a desert area of San Juan, Argentina. We analysed lizard food preferences, taxonomic and functional diversity, dissimilarity and the relationship between morphological variables and prey item frequency. We found that the diet of six species, at both sites, was focused on Hymenoptera (< 80%), whereas secondary and accessory items varied widely between species and sites, with 40% dissimilarity. Prey at the cultivated site were more abundant, rich and diverse than in the non‐cultivated site, with 20% dissimilarity in species composition. Functional diversity showed redundancy when comparing morphological and dietary traits. Results suggest that the greater variation in the diet of species at the cultivated site is likely due to a higher diversity of prey available. We determined that diet could be a limiting factor for L. cuyanus, because there are no native plants at the cultivated site, whereas the remaining species opted for increasing their intake of Hymenoptera.

Agricultural exploitation and physiographic location in the availability of nutrients to the soil of Diyala Governorate

The study area was chosen to include three physiographic sites on the Diyala River, as it is located in the village of Umm Al-Azam between longitudes 33.71785 east and latitudes 44.6185 north. There are four pedons in each A physiographic unit, two of which are in cultivated sites and the other two are in unexploited agricultural sites, so the total of the studied pedons is twelve. The results of laboratory analysis showed that the lowest content of available nitrogen for the cultivated sites was in the soils of river levees and the highest content in the soils of the river basins, while in the abandoned soil sites, it was the lowest content in the soils of the river basins and the highest content in the soils of depressions, and that the variance of the available nitrogen content in the soils of the cultivated pedons sites was moderate. The results indicated that the available phosphorous content in the sites of cultivated pedons soils ranged between 17.25 – 40.24 mg kg-1 as it was the lowest content in river levee and the highest in the depressions soils, while the available phosphorous content in the soils of the abandoned pedons sites ranged between 19.19 - 43.00 mg kg-1 as it was the lowest content in river basins and the highest content in depressions soils, while the variance of phosphorus in the cultivated soils pedons was of slight variation available. The available potassium content in the soils of the planted pedons sites ranged between 175.60 - 255.17 mg kg-1 , as it was the lowest content in the river levee and the highest in the soils of the river basins. The available potassium content in the soils of the abandoned pedons sites ranged between 170.64 - 257.45 mg kg-1 , where the lowest content of the available potassium was in the river levee soils, and the highest was in the depressions soils. Also, the variance of the available potassium in the pedons' soils was very little. As for the effect of the interaction between agricultural exploitation and physiographic sites and horizons in the characteristics of the study area, the results of the statistical analysis indicated that all study indicators represented by sites, type of use, horizons and their interactions did not have a significant effect of increasing nitrogen in the soil of the study area, as well as phosphorous and potassium. Keywords: N, P, K, nutrients, physiographic location, agricultural exploitation.

The effect of agricultural exploitation and physiographic location on the soil particle size distribution for soils in Diyala Governorate

The study area was chosen to include three physiographic sites on the Diyala River, as it is located in the village of Umm Al-Azam between longitudes 33.71785 east and latitudes 44.6185 north. There are four pedons in each A physiographic unit, two of which are in cultivated sites and the other two are in unexploited agricultural sites, so the total of the studied pedons is twelve. The results of laboratory analyses showed that the sand content in the physiographic units of the cultivated soils ranged between 151.19 - 583.20 g kg-1 , as it was noted that the highest content was in the soils of river basins, while in the physiographic units of the abandoned soils, the sand content ranged between 146.62 - 600.50 g kg -1 , as its highest content was in soils River basins as well. As for the silt particle, the results showed that its content in the physiographic units of the cultivated soil ranged between 170.00 - 543.11 g kg-1 , as it was noted that its highest content was in the soils of the depression unit, while in the physiographic units of the abandoned soils, the content of the silt ranged between 54.42 - 553.01 g kg-1 , as the highest content was in pedons soils the river. As for the particle clay, its content in the cultivated physiographic units ranged between 52.10 - 375.67 g kg-1 , as the highest content was in the soils of river levee, while in the soils of the abandoned physiographic units, it ranged between 54.42 - 335.57 g kg-1 , which was the highest value for it. When soils levee of rivers . Keywords: particle, distribution, physiographic location, agricultural exploitation

Impacts of reclamation marsh restoration on greenhouse gas emission in the Sanjiang Plain, China.

To understand the variations in greenhouse gas fluxes during the process of returning cropland to wetland in the Sanjiang Plain, we selected naturally restored wetlands of 4, 7, 11, 16 and 20 years as research objects to compare with a cultivated site (soybean plantation for 13 years) and an uncultivated marsh dominated by Deyeuxia purpurea and Carex schmidtii. We measured carbon dioxide (CO2) and methane (CH4) fluxes using a static chamber-gas chromatography and explored the main influencing factors. The results showed that there were seasonal variations in growing-season CO2 and CH4 fluxes of the restored wetlands, with the seasonal trends in greenhouse gases becoming gradually similar to that of natural marsh with increasing restoration time. The mean growing-season CO2 fluxes increased during the early stage of restoration, but then decreased during the late stage, which decreased from 893.4 mg·m-2·h-1 to 494.0 mg·m-2·h-1 in the 4-year and 20-year sites, respectively. Mean CH4 fluxes increased with restoration time, ranging from a weak CH4 sink (soybean fields, -0.6 mg·m-2·h-1) to a CH4 source of 87.8 mg·m-2·h-1(20-year restored site). The CH4 fluxes of experimental plots were consistently lower than that of natural marsh (96.4 mg·m-2·h-1). Increases in water level and soil conductivity resulting from restoration were the main driving factors for the decrease in CO2 fluxes. The increases in water level and soil dissolved organic carbon resulting from restoration were the primary drivers for the increase of CH4 fluxes in the restored wetlands. The global warming potentials increased with restoration time, ranging from 27.8 t·CO2-eq·hm-2(soybean fields) to 130.8 t·CO2-eq·hm-2(plot of 20-year restoration), which gradually approached that of natural marsh (156.3 t·CO2-eq·hm-2). The emission of GHGs from restored wetlands in the Sanjiang Plain gradually approached those of natural marsh. Further monitoring is required to identify the maturity of restored wetlands for achieving greenhouse gas emissions equivalent to that of natural marshland.

Compositional changes in the humin fraction resulting from the long-term cultivation of an Irish grassland soil: Evidence from FTIR and multi-NMR spectroscopies

Soil humin (HN), a major long-term sink for carbon in the pedosphere, plays a key role in the global carbon cycle, and has been less extensively studied than the humic and fulvic acids components. There are increasing concerns about the depletions of soil organic matter (SOM) arising from modern soil cultivation practices but there has been little focus on how HN can be altered as the result. This study has compared the HN components in a soil under cultivation for wheat for >30 years with those from an adjacent contiguous soil that had been under long-term grass for all that time. A urea-fortified basic solution isolated additional humic fractions from soils that had been exhaustively extracted in basic media. Then further exhaustive extractions of the residual soil material with dimethyl sulfoxide, amended with sulphuric acid isolated what may be called the “true” HN fraction. The long-term cultivation resulted in a loss of 53 % soil organic carbon in the surface soil. Infrared and multi-NMR spectroscopies showed the “true” HN to be dominated by aliphatic hydrocarbons and carboxylated structures, but with clear evidence for lesser amounts of carbohydrate and peptide materials, and with weaker evidence for lignin-derived substances. These lesser-amount structures can be sorbed on the soil mineral colloid surfaces and/or covered by the hydrophobic HN component or entrained within these which have strong affinities for the mineral colloids. HN from the cultivated site contained less carbohydrate and more carboxyl groups suggesting slow transformations took place resulting from the cultivation, but these were much slower than for the other components of SOM. It is recommended that a study be made of the HN in a soil under long-term cultivation for which the SOM content has reached a steady state and where HN will be expected to dominate the components of SOM.

Mapping abandoned cropland using Within-Year Sentinel-2 time series

Against the background of the COVID-19 pandemic and various armed conflicts, the world is experiencing an unprecedented food crisis. The reclamation of abandoned cropland with food production potential may increase the global food supply in a short period of time, ensuring food security. At present, the extraction of abandoned cropland is mainly based on low- and medium-resolution remote sensing image data, making it difficult to extract fragmented areas in mountainous regions and to distinguish between abandoned cropland and transitional classes (such as fallow cropland). We developed a change-detection method based on within-year Sentinel-2 time series to extract cropland abandoned from 2018 to 2021 and defined four types of croplands, namely spontaneously abandoned, induced abandoned, fallow, and lost cropland, using Linxia County in mountainous China as the study region. First, cropland objects were generated from multi-temporal Sentinel-2 images using the multi-resolution segmentation method, and the land use map of Linxia County from 2017 to 2021 was drawn using random forest classifier. Second, through defining and identifying different cropland types, the interannual dynamic changes in cropland from 2018 to 2021 were extracted by analyzing the annual land use change trajectory. Third, by analyzing the normalized difference vegetation index (NDVI) time series of cropland within-year, the active and cultivated cropland sites within-year were extracted by threshold segmentation. Finally, the changes in the four cropland types were extracted by intersecting the two result types. Our method captured the object level changes well (overall mapping accuracy = 93 ± 5 %), and the extraction accuracy of abandoned cropland reached 81 ± 2 %. Abandoned cropland was mostly located in areas of medium quality and with a moderate distance from rural settlements. Reclamation can potentially increase the grain production in Linxia County by at least 3.6 % and needs to be combined with the local natural geography and human activities. Our method is a robust method for extracting abandoned cropland and may be applied to other research related to land use change.

Exploring the Phytochemical Profiles and Antioxidant, Antidiabetic, and Antihemolytic Properties of Sauropus androgynus Dried Leaf Extracts for Ruminant Health and Production

Sauropus androgynus has become an essential plant in pharmaceutical formulations due to its beneficial antioxidant phytochemical components, participating in the antioxidant defense system and playing an important role in protecting human health. However, no research has been conducted on ruminant animals. This study aimed to evaluate the phytochemical profiles and biological potential of S. androgynus leaf extracts for ruminant health. Methanolic and hexanoic extracts from each commercially and noncommercially cultivated site were prepared over the course of five consecutive months. By means of HPLC-DAD, vitamins (ascorbic acid), essential oils (eugenol), tannins (gallic acid), cinnamic acids (caffeic acid, syringic acid, p-coumaric acid, sinapic acid and ferulic acid), and flavonoids (catechin, rutin, myricetin, quercetin, apigenin, and kaempferol) were detected. Variations in phytochemical composition were depending on solvent type but not on cultivation site or sample period. Methanolic extracts contained more phytochemicals than hexanoic extracts. Ascorbic acid and rutin were discovered to be the two most abundant phytochemicals in the methanolic extract of S. androgynus leaf, followed by essential oils, cinnamic acids, and tannins. In comparison to hexanoic extract, methanolic extract of S. androgynus demonstrated to be more efficient against oxidation scavenging: 1,1-diphenyl-2-picrylhydrazyl (IC50 = 13.14 ± 0.055 (mg/mL)), nitric oxide (IC50 = 55.02 ± 1.338 (mg/mL)) and superoxide (IC50 = 25.31 ± 0.886 (mg/mL)), as well as α-glucosidase inhibitory activity (IC50 = 9.83 ± 0.032 (mg/mL)). Similarly, methanolic was found to be more protective than hexanoic against oxidative damage in ruminant erythrocytes, with IC50 values (mg/mL) for hemoglobin oxidation, lipid peroxidation, and hemolysis of 11.96 ± 0.011, 13.54 ± 0.012, and 5.940 ± 0.005, respectively. These findings suggested that the leaves of S. androgynus are a prospective source of phytochemical substances with health-promoting qualities for ruminant production.

Влияние органоминеральных питательных комплексов на урожайность малины (Rubus idaeus L.) в условиях Московского региона

The article presents the results of studies the influence of organomineral fertilizers complex «Beliy Zhemchug» on the yield and quality of raspberries (Rubus idaeus L.). The experiment was conducted on the Main Botanical Garden named after N.V. Tsitsin RAS territory, at the Laborato-ry of Cultivated Plants collection site. The objects of the study were the raspberry varieties ‘Zheltiy Guigant’, ‘Cascad’, ‘Solnishko’, ‘Novost’ Kuzmina’; organomineral complexes of fertilizers 'Beliy Zhemchug Antifreeze' (1% solution), 'Beliy Zhemchug Universalniy' (1% solution), 'Beliy Zhem-chug Drip' (1% solution), 'Beliy Zhemchug PhytoZatshita' (5% solution), 'Beliy Zhemchug StopKlop' (5% solution). Two-factor ANOVA did not show a significant effect of treatment with a phytomodulator on the raspberry fruits’ parameters. However, the fruits’ length, width and weight of ‘Zheltiy Guigant’ and ‘Cascad’ have been slightly increased, and the fruits have become more equal. ‘Solnishko’ showed a reverse reaction to the treatment. ‘Novost’ Kuzmina’ fruits parame-ters have been slightly increased while their uniformity have been reduced. The treatment had a positive effect on the sugar amount, fruits density and external evaluation. All these parameters are strongly directly related with fruits transportability, storage and original appearance retaining. Keywords: RASPBERRY, PRODUCTION, RUBUS IDAEUS L, CHEMICAL COMPLEX

Spatial Analysis of Cultivated Land Productivity, Site Condition and Cultivated Land Health at County Scale.

Cultivated land is a fundamental factor related to the social stability and sustainable development of the whole country. However, the safety of quantity and quality of cultivated land has decreased year by year, resulting in great challenges to the sustainable development of cultivated land. Cultivated land productivity, site conditions, and soil health jointly determine the sustainable development potential of cultivated land. Analyzing and calculating the coupling and cooperative relationship between these three subsystems can provide a theoretical and methodological reference for protecting and zoning cultivated land resources. Using Jiangyou City as a case study, this paper constructs a coupling coordination degree model of cultivated land productivity, site conditions, and soil health assessment systems in different geomorphic regions, and comprehensively analyzes the level of sustainable development of cultivated land in the study area. The results show that there are differences in the development potential of cultivated land resources in the mountainous regions in the north, the hilly regions in the center, and the plain regions in the south of Jiangyou City. The coupling coordination index of the three regions were calculated as 0.34, 0.51, and 0.63, respectively, for which the overall average coupling coordination index is 0.57; notably, it only reaches the “barely coordination” level. Based on our analysis results, the cultivated lands in Jiangyou City are classified into the following zones: core protection zone, dominant remediation zone, and key regulation zone. The cultivated land located in the core protection zone has a high coupling coordination index, which can be used as the preferred area for the delimitation of high standard basic farmland and permanent basic farmland. For the cultivated land located in the dominant remediation zone, the development of its subsystems is unbalanced. Comprehensive land improvement projects can be carried out in this zone to improve the overall quality. For the cultivated land located in the key regulation zone, it is recommended to implement projects such as returning farmland to forests to improve land use efficiency. In particular, the evaluation index system constructed in this paper is sufficiently representative, as it can support the classification, quality improvement, and sustainable use of cultivated land. Thus, other similar countries and regions can learn from the evaluation system constructed in this paper.

Occurrence Of Lac Insect And Its Host Plants In Madhya Pradesh

Lac insect occurrence was observed in 302 locations, and samples of 267 populations belonging to Rangeeni and 35 from Kusmi strains were collected. A total of 17 host plants belonging to 7 genera were observed with live lac encrustation. Maximum frequency of occurrence was seen on Palas in 133 sites (44.03%) followed by Pipal in 97 sites (32.11%), Kusum- 35 sites (11.60%), Ber- 15 sites (4.97%) and other 13 lac hosts in 22 sites. Maximum lac insect occurrence in terms of sites were reported from Seoni (49- 16.2%), followed by Mandla (42- 13.9%), Balaghat (39- 12.9%), Hoshangabad (13- 4.3%), Chhindwara (10- 3.31%) and other 41 districts of Madhya Pradesh (149 sites). During the study, 2 colour variants were observedthese are crimson (236 sites) and yellow (62 sites0 and crimson-yellow (mixed- 4 sites). The study listed 167 lac cultivation sites, of which the maximum cultivated sites were from Seoni district (49 sites- 29.30%) followed by Balaghat (39 sites- 23.40%), Mandla (30 sites-18.00%), Hoshangabad (9- 5.39%) and other ten districts (40 sites). In natural condition total 135 lac insect occurrence sites were observed and of these maximums were observed in Rajgarh, Morena, Shivpuri (each in 8 sites- 5.93%) followed by Sagar, Indore, Mandsaur, Agar Malwa each (6 sites- 4.44%) and other 87 sites in 32 other districts.

Study of the Agglomeration Characteristics of Cultivated Land in Underdeveloped Mountainous Areas Based on Spatial Auto-Correlation: A Case of Pengshui County, Chongqing, China

The economic and social orientation of cultivated land in underdeveloped mountainous areas is obvious. A study of the spatial agglomeration characteristics of cultivated land quality can provide guidance for regional economic and social development. Taking Pengshui County, Chongqing, China as the study area, the spatial agglomeration characteristics of cultivated land quality indexes at county, township and village levels were analyzed by using the auto-correlation analysis method. The results showed that: (1) At different spatial scales, the cultivated land quality index showed spatial agglomeration characteristics. (2) Moran’s I values of the cultivated land quality index at county, township and village level decreased successively, but three indexes still showed significant positive spatial correlation. (3) The spatial scale affects the spatial agglomeration of the cultivated land quality index, and its influence is physical, with a utilization and economic quality grade index from large to small. In underdeveloped mountainous areas, the spatial agglomeration characteristics of township scale and physical quality grade index are the most stable and significant, which can be used as the direct basis for zoning of cultivated land protection and site selection of rural residents’ agglomeration points.

Irrigation Water Impact on Soil Properties in Arid Oued-Souf Region, Southeast Algeria

The perimeters of the Oued-Souf region are irrigated by salty water coming from the phreatic water and thus progressive salinization of the soil occurs. This study aims at a qualitative analysis of the evolution of the salinity in the soils irrigated by pivot irrigation for several years. For this, three plots were irrigated by pivots in each agricultural region. The choice of these 3 plots is justified by the number of years of their cultivation: plot 1 has been cultivated and irrigated for 2 years (2016–2017), plot 2 has been cultivated and irrigated for 5 years (2016–2020) were studied and compared to the controlled soil not irrigated. The irrigation is done by sprinkling with mineralized water from the phreatic water. The results obtained showed that the irrigation water is characterized by high salinity and low sodium adsorption ration (SAR). Sodium and chloride contents are excessive in sprinkler irrigation mode. The evolution of salinity in irrigated soils between 2 and 5 years was very significant compared to the control (non-irrigated). The salinity goes from 0.38 dS/m in the control site classified as low salinity to 1.54 dS/m in the cultivated site for the 5 years classified as high salinity soil. The geochemical facies at the three study regions after irrigation are sulfate-calcium. A significant correlation is observed between calcium and sulfate with electrical conductivity (EC), so the salinity of our soils is dominated by sulfate. These results are confirmed by statistical analysis of the data (PCA), which revealed that salinity is heavily influenced by Mg2+, Ca2+, SO42- in the topsoil. Keywords: Hydrochemical; Irrigation water; Oued-Souf area; Phreatic aquifer; Salinity; Soil; Statistical analysis.

Genomic Analyses of Wild and Cultivated Bacanora Agave (Agave angustifolia var. pacifica) Reveal Inbreeding, Few Signs of Cultivation History and Shallow Population Structure.

Due to the recent increase in demand for agave-based beverages, many wild agave populations have experienced rapid decline and fragmentation, whereas cultivated plants are now managed at monocultural plantations, in some cases involving clonal propagation. We examined the relative effect of migration, genetic drift, natural selection and human activities on the genetic repertoire of Agave angustifolia var. pacifica, an agave used for bacanora (an alcoholic spirit similar to tequila) production in northwestern Mexico. We sampled 34 wild and cultivated sites and used over eleven thousand genome-wide SNPs. We found shallow genetic structure among wild samples, although we detected differentiation between coastal and inland sites. Surprisingly, no differentiation was found between cultivated and wild populations. Moreover, we detected moderate inbreeding (FIS ~ 0.13) and similar levels of genomic diversity in wild and cultivated agaves. Nevertheless, the cultivated plants had almost no private alleles and presented evidence of clonality. The overall low genetic structure in A. angustifolia var. pacifica is apparently the result of high dispersibility promoted by pollinators and the possibility of clonal reproduction. Incipient cultivation history and reliance on wild seeds and plants are probably responsible for the observed patterns of high genetic connectivity and considerable diversity in cultivated samples.

Assessment of Fungi Species Associated with a Multicultural Orchard and Cultivated Land in Bingham University Landscape, Karu Nasarawa State, Nigeria

Assessment of fungal species associated with a multicultural orchard and cultivated land in Bingham University landscape was carried out, with the ultimate aim of identifying the fungi species present in soil under different agricultural practices. A total of 30 soil samples were collected and the composite from each land use pattern was analyzed in the laboratory using standard methods. Soil type, percentage Soil Moisture (SM), percentage Organic Carbon (OC) and percentage Organic Matter (OM) were measured using standard methods; fungi species were isolated and identified on the basis of mycelia and spore characteristics, after staining with lactophenol-in-cotton blue. The results showed that, four types of soil exist in the sites including sandy, clayey, silt and loamy. SM ranges between 3.6% -5.7%, and OC in the sandy soil was the highest 1.01% in the orange plantation (Op5) followed closely by loamy soil on cultivated site C with 0.97% OM and 0.56% OC and least in clay soil with 0.72% OM and 0.42% OC. The results of colony forming unit per gram (cfu/g)in relation to land use type, Cultivated Site C (CC1-CC5) had the highest (262 cfu/ g) and mango plantation (Mp1-Mp5) had the least with 156 cfu/g. Pictorial representation of isolated fungal species are indicative of suspected presence of Aspergillus Spp, Mucor Spp, Cladosporium Spp, Fusarium Spp, Aspergillus Spp etc. This qualitative study concluded that fungal species population in the soil depends on the management practice in place and the moisture content of the soil.

气候变化对柴胡与狭叶柴胡适生分布的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 气候变化对柴胡与狭叶柴胡适生分布的影响 DOI: 10.5846/stxb202108242369 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家中医药管理局全国中药资源普查项目（GZY-KJS-2018-004）；全国第四次中药资源普查黑龙江专项（2018hljzyzypc-12）；黑龙江省自然科学基金（C2018038） Prediction of distribution pattern and change of suitable areas of Bupleurum chinense and Bupleurum scorzonerifolium under climate change in China Author: Affiliation: Fund Project: 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:研究气候变化下物种适生区的分布格局与变迁，对于物种的保护和资源的可持续利用具有重要的理论和实践意义。选取柴胡（Bupleurum chinense）与狭叶柴胡（Bupleurum scorzonerifolium）在中国地域内的381个有效分布点和36个环境因子，利用MaxEnt模型模拟当前以及未来（2050和2070年）两种气候情景下（RCP4.5和RCP8.5）其适生区的分布格局，并分析了制约其适生区分布的主导环境因子。结果表明：（1）影响柴胡适生区分布的主导环境因子为最湿月份降水量、最干季度平均温度以及海拔。影响狭叶柴胡适生区分布的主导环境因子为最湿月份降水量、温度季节性变化标准差以及海拔；（2）当前气候条件下，柴胡适生区总面积为1.4755×106km2，约占我国国土面积的15.37%，中、高度适生区主要分布在陕西南部、山西东部、甘肃东南部、山东中部、河北中西部等地；狭叶柴胡适生区总面积为1.8034×106km2，约占我国国土面积的18.78%，中、高度适生区主要分布在黑龙江西部和东部、内蒙古中部和东北部、河北北部、陕西中部等地。（3）未来气候背景下，两种柴胡总适生区面积呈现增加趋势。柴胡适生区分布质心向东北方向的高纬度地区迁移，狭叶柴胡适生区分布质心向西部方向的高海拔地区迁移。 Abstract:It is of great theoretical and practical importance to study the distribution patterns and changes of species suitable geographical distribution areas under the background of climate change for the protection of species and the sustainable use of resources. In this study, 381 effective distribution sites of Bupleurum chinense and Bupleurum scorzonerifolium in China (excluding duplicate, invalid and cultivated distribution sites) and 36 environmental factors (terrain, soil and climate data) were selected. Baesd on the data mentioned above, the spatial distribution patterns of the suitable geographical distribution areas, B. chinense and B. scorzonerifolium, were simulated by the maximum entropy (MaxEnt) model under current climate and two climate scenarios (RCP4.5 and RCP8.5) for the future (2050 and 2070), respectively. Meanwhile, the dominant environmental factors that restrict the distribution of these two species suitable geographical distribution areas were analyzed. The results show that (1) Precipitation of wettest period (Bio13) was the most important environmental factor affecting the suitable geographical distribution areas of B. chinense, followed by mean temperature of driest quarter (Bio09), and altitude (Elevation). In the same way, precipitation of wettest period (Bio13), temperature seasonality (Bio04), and altitude (Elevation) are the dominant environmental factors that affect the distribution of B. scorzonerifolium suitable geographical distribution areas. (2) Under the current climate conditions, the total area of suitable geographical distribution areas for B. chinense is 1.4755×106km2, which is account for about 15.37% of the total land area of China. And the middle and high suitable geographical distribution areas are mainly distributed in southern Shaanxi, eastern Shanxi, southeastern Gansu, central Shandong, central and western Hebei, etc. At the same time, the total area of suitable geographical distribution areas for B. scorzonerifolium is 1.8034×106km2, accounting for approximately 18.78% of the total land area of China, of which the middle and high suitable geographical distribution areas are mainly distributed in western and eastern Heilongjiang, central and northeastern Inner Mongolia, northern Hebei and central Shaanxi, etc. (3) Under the background of future climate change, the total suitable geographical distribution area of two species of Bupleurum both shows an increasing trend. In term of the migration study of suitable geographical distribution geometric center, the suitable geographical distribution geometric center of B. chinense will step by step move to the high latitude area in the northeast, while the suitable geographical distribution geometric center of B. scorzonerifolium will gradually migrate to the high altitude areas in the west. 参考文献 相似文献 引证文献

Diversity and function of rhizosphere microorganisms between wild and cultivated medicinal plant Glycyrrhiza uralensis Fisch under different soil conditions.

Glycyrrhiza uralensis Fisch is a widely cultivated traditional Chinese medicine plant. In the present study, culture-independent microbial diversity analysis and functional prediction of rhizosphere microbes associated with wild and cultivated G. uralensis Fisch plant (collected from two locations) were carried. Soil physicochemical parameters were tested to assess their impact on microbial communities. A total of 4428 OTUs belonging to 41 bacterial phyla were identified. In general, cultivated sample sites were dominated by Actinobacteria whereas wild sample sites were dominated by Proteobacteria. The alpha diversity analysis showed the observed species number was higher in cultivated soil samples when compared with wild soil samples. In beta diversity analysis, it was noticed that the weighted-unifrac distance of two cultivated samples was closer although the samples were collected from different regions. Functional annotation based on PICRUST and FAPROTAX showed that the nitrogen metabolism pathway such as nitrate reduction, nitrogen fixation, nitrite ammonification, and nitrite respiration were more abundant in rhizosphere microorganisms of wild G. uralensis Fisch. These results also correlate in redundancy analysis results which show correlation between NO3--N and wild samples, which indicated that nitrogen nutrition conditions might be related to the quality of G. uralensis Fisch.

Impact of weather changes on the potato cultivation quality with the LEISA system

The aspect of potato cultivation well known to most farmers is closely related to the climatology of the cultivated site. Therefore, this study aims to obtain the basic information on climatic change in potato cultivation quality using the LEISA system or in potato cultivation, compost is used as fertilizer at a dose of 10-30 tonnes/ha. The experiment was designed based on four treatments namely, (1) cultivation in normal weather conditions from April - June 2019, (2) in foggy air conditions from July to September 2019, (3) in extremely hot conditions from October to December 2019, and (4) in extremely rainy conditions from January to March 2020. The parameters observed were (1) microclimates around the plants, (2) the condition of the growing media depth 0-30 cm, (3) plant growth, and (4) productivity. The changes from normal to foggy, extremely rainy, and hot weather had impacts on soil temperature by 22.1±5.2%, 8.6±2.2%, and 10.3±5.9% respectively. In extremely hot and rainy weather, the cation exchange capacity (CEC) value was low by 22.1±0.16 and 23.8±0.21 meq/100g of dry soil. The extremely hot, rainy, and foggy weather reduced the productivity of potato plants by 32.13–60.2%, 19.5– 43.0%, and 16.7–18.0% respectively. In addition, they also reduced the quality of potato tubers by 19.9–94.7%, 26.0–62.9%, and 8.8–15.9% respectively.