For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5...For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L^-1 and 500 mg·L^-1 and combinational treatment of scarification with gibberellic acid of 250 mg·L^-1 and 500 mg·L^-1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.展开更多
Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and biodiversity.To better understand the impacts of biological invasion...Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and biodiversity.To better understand the impacts of biological invasions on soil,we compared topsoil physiochemical properties at sites with invasive alien tree species(Prosopis juliflora),native tree species(Prosopis cineraria,Acacia tortilis,and Acacia ehrenbergiana),and mixed tree species in Hormozgan Province of Iran in May 2018.In this study,we collected 40 soil samples at a depth of 10 cm under single tree species,including P.juliflora,P.cineraria,A.tortilis,and A.ehrenbergiana,as well as under mixed tree species.The results showed that organic matter,moisture,potassium,calcium,nitrogen,and magnesium in topsoil at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria were higher than that at sites where P.juliflora was present(P<0.05).Sodium at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria and P.juliflora was lower as compared to that at sites with just A.tortilis and A.ehrenbergiana.Electrical conductivity was lower at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria,and it was higher at sites with mixed Acacia and P.juliflora trees.Based on the generally more positive effect of native Acacia and P.cineraria on topsoil physiochemical properties as compared to the P.julifora,afforestation with native tree species is preferable for soil restoration.In addition,due to the negative effects of P.julifora on soil properties,P.julifora spread should be better managed.展开更多
This study investigates the potential of native biocontrol agents(BCAs)as controls against Ganoderma lucidum causing root rot mortality in Indian mesquite.The disease is prevalent in sandy soils where trees grow under...This study investigates the potential of native biocontrol agents(BCAs)as controls against Ganoderma lucidum causing root rot mortality in Indian mesquite.The disease is prevalent in sandy soils where trees grow under rainfed conditions.In addition,a beetle namely A canthophorus serraticornis damages the roots,resulting in increasing vulnerability of the host thereby allowing easy of the pathogen.In dual culture tests,Ganoderma infected cowpea root bit experiment and compatibility with insecticides revealed that the three BCAs(Trichoderma longibrachiatum,T.harzianum,and Aspergillus nidulans)significantly inhibited G.lucidum mycelial growth.The highest mycelial growth inhibition(47.6%)was recorded after 96 h followed by 39.8%and 29.3%at 72 and 48 h,respectively,by T.longibrachium.Cell free filtrates of T.longibrachiatum,T.harzianum,and A.nidulans were superior in inhibiting mycelium growth.A low concentration(3 ml)of T.longibrachiatum was more effective in inhibiting mycelium growth compared to other BCAs.Both P rosopis julifl ora compost and onion residue compost amendments as food substrates favored the growth of these BCAs,which ultimately reduced the viability of Ganoderma-colonized root bits of cowpea.Studies on compatibility between insecticides and BCAs suggests that T.longibrachiatum,harzianum and A.nidulans can be combined with phorate or chloropyriphos(both organophosphates)at variable concentrations if amended together for partially infected trees,or as a prophylactic measure in healthy trees.These studies demonstrate that there is considerable opportunity for using native BCAs against G.lucidum in managing root rot disease.展开更多
Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of th...Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of the compounds by standard chromatographic techniques.With the help of DART-MS,chemical fingerprint of raw plant parts were generated,which revealed the presence of piperidine alkaloids in leaf,pod and flower.A comparative study of the distribution pattern,showed variation in the presence and distribution of these alkaloids in various parts of P.juliflora.The leaves and pod displayed the largest alkaloid pattern with a total of 12 different alkaloids in each part,whereas only 4 alkaloids were present in flower.Alkaloids:julifloridine,prosopine,prosopinine and prosafrinine were ubiquitously distributed in all the alkaloid rich plant parts.Juliprosopine was pre-eminet alkaloid in leaf,whereas pod and flower displayed copious amounts of julifloridine.展开更多
This study was aimed to determine the extent to which Prosopis species had invaded four settlements (Bokspits, Rappelspan, Vaalhoek and Struizendam) located in the Kgalagadi Desert south west of Botswana, investigate ...This study was aimed to determine the extent to which Prosopis species had invaded four settlements (Bokspits, Rappelspan, Vaalhoek and Struizendam) located in the Kgalagadi Desert south west of Botswana, investigate the perceptions of the communities about the existence of the species in their environment and assess possible control options for the spread of Prosopis plants in the area. Prosopis plants were sampled in 42 quadrats of 625 m2 along a 70 km Prosopis invasion gradient from Struizendam to Rappelspan. Using the Global Positioning System (GPS), the locations of all quadrats were established. The distribution map of Prosopis plants was produced using ArcGIS 9.2 (ESRI Inc.). Questionnaire survey and focused group discussions were used to collect data on the perceptions of rural communities about the species. A total of 342 respondents comprising 139 males and 203 females were interviewed, and four focussed group discussions were conducted. The results indicated that the invasion of Prosopis species was prominent in and around settlements suggesting that anthropogenic activities had a significant role in the spread of Prosopis plants in the area. The perceptions of rural communities about Prosopis plants appeared to be moulded by the impacts of the plants on their livelihoods as well as their micro-economic status. The respondents (71.30%) expressed the view that the invasion of Prosopis species negatively affected the livelihoods of the communities in the study area. They identified eradication as the preferred method of controlling the spread of Prosopis plants. On the contrary, this study recommended the integrated environmental management paradigm as the best options for the control of the spread of Prosopis plants in the area.展开更多
Background:Trees and forests in drylands help mitigate the challenges through provision of economic products and vital environmental services such as habitat for biodiversity,prevention of erosion and desertification,...Background:Trees and forests in drylands help mitigate the challenges through provision of economic products and vital environmental services such as habitat for biodiversity,prevention of erosion and desertification,regulation of water,microclimate,and soil fertility.The condition and changes in dry forests can be assessed by using ecological indicators able to quantify spatial and temporal changes in vegetation.One of the ways to determine the condition of the forest is to study the dominant tree species and its regeneration.Our study aimed to assess whether the abundance of Prosopis flexuosa saplings is affected by environmental and biological factors.Results:To evaluate the first variables we used data from remote sensing such as satellite images and Aster Global Digital Model(GDEM).The second set of variables was about exotic and native ungulates and we used feces of these animals and camera traps to take data.We found that sapling abundance related positively to sandy substrates and negatively to Wetness Index.On the other hand,in relation to biological variables,the abundance of saplings was positively affected by density of adult trees and by number of seeds dispersed by equines,but space use by Lama guanicoe had a negative relationship with saplings.This research shows that P.flexuosa saplings are benefited from sandy substrates and the conditions around adult trees.In addition to this,we found that exotic ungulates in low densities have neutral(i.e.cattle)or positive(i.e.equines)effects on sapling abundance.Conclusions:Based on these findings,we conclude that regeneration of the population of P.flexuosa in our study area has no major problems.In addition,we corroborated that the presence of exotic and domestic ungulates in low densities does not have deleterious consequences for saplings of the dominant tree,P.flexuosa.展开更多
Background:Investigating new therapies for inflammatory bowel disease among natural products has recently been gaining attention.Although Prosopis farcta has repeatedly been mentioned in traditional Persian medicine a...Background:Investigating new therapies for inflammatory bowel disease among natural products has recently been gaining attention.Although Prosopis farcta has repeatedly been mentioned in traditional Persian medicine as a therapeutic option for inflammatory bowel disease,no evidence-based investigations have been conducted on this topic.The aim of this study was to assess the impact of P.farcta on acetic acid-induced colitis in rats.Methods:A hydroalcoholic extract of P.farcta fruits was prepared.Thirty-six adult Wistar rats were divided into six groups,and colitis was induced in five groups,except the sham group,using acetic acid solution.The animals received distinctive daily doses of P.farcta(50,75,and 100 mg/kg/day,p.o.)and dexamethasone(1 mg/kg/day,i.p.)as standard treatment for two progressive days,starting from colitis induction.Microscopic and histopathological examinations were performed on inflamed colonic tissue.Tissue concentrations of interleukin-1βand tumor necrosis factor-αwere assessed using enzyme-linked immunosorbent assay kits.To identify the role of oxidative stress in ulcerative colitis,the levels of malondialdehyde and myeloperoxidase were measured in colon tissues.Results:Treatment with all concentrations of P.farcta attenuated inflammation and ulcers compared with saline treatment in the control group(P<0.01 for 50 mg/kg;P<0.001 for 75 and 100 mg/kg/day).The best suppression of tumor necrosis factor-αand interleukin-1βwas observed at a dose of 100 mg/kg P.farcta(P<0.001).This dose showed the best effect in reducing myeloperoxidase and malondialdehyde in ulcerative colitis-induced rats(P<0.001).Conclusion:P.farcta can be considered a promising candidate for treating ulcerative colitis;thus,it requires further confirmation by clinical trials.展开更多
Arbuscular mycorrhizal (AM) fungi associated with Prosopis cineraria (Khejri) were assessed for their qualitative and quantitative distribution from eight districts of Rajasthan. A total of three species of Acaulo...Arbuscular mycorrhizal (AM) fungi associated with Prosopis cineraria (Khejri) were assessed for their qualitative and quantitative distribution from eight districts of Rajasthan. A total of three species of Acaulospora, one species of Entrophospora, two species of Gigaspora, twenty-one species of Glomus, seven species of Sclerocystis and three species of Scutellospora were recorded. A high diversity of AM fungi was observed and it varied at different study sites. Among these six genera, Glomus occurred most frequently. Glomus fasciculatum, Glomus aggregatum, and Glomus mosseae were found to be the most predominant AM fungi in infecting Prosopis cineraria. Acaulospora, G. fasciculatum, Sclerocystis was found in all the fields studied, while Scutellospora species were found only in few sites. A maximum of thirty-six AM fungal species were isolated and identified from Jodhpur, whereas only thirteen species were found from Jaisalmer. Spores of Glomusfasciculatum were found to be most abundant under Prosopis cineraria.展开更多
An experiment was initiated in 2008 to evaluate the impact of irrigation regimes on germination and growth patterns of seedlings of Prosopis cineraria in the arid areas of Thar, India. Seeds collected from dried pods ...An experiment was initiated in 2008 to evaluate the impact of irrigation regimes on germination and growth patterns of seedlings of Prosopis cineraria in the arid areas of Thar, India. Seeds collected from dried pods of P cineraria were sown in polybags placed in nursery beds. Different irrigation regimes were provided to different beds and data regarding germination and growth were recorded to study natural regeneration. The study revealed that irrigation regimes significantly affected the germination and growth of P cineraria under nursery conditions. The germination rate declined as the irrigation regime shifted from a daily to a fortnightly ba- sis. Height of the seedlings also declined with a decrease in the intensity of irrigation. Thus, it can be concluded that germination and growth of seedlings of P cineraria under nursery conditions can be enhanced by providing irrigation at regular intervals.展开更多
The morphological variability of Prosopis africana in its natural range (which includes three climate zones: Guinean zone, Sudano-Guinean zone and Sudanese zone) of Benin was studied on the basis of forest inventory c...The morphological variability of Prosopis africana in its natural range (which includes three climate zones: Guinean zone, Sudano-Guinean zone and Sudanese zone) of Benin was studied on the basis of forest inventory carried out in three different vegetation types (savannah, fallow and field). The data recorded in 139 plots of 1000 m2 each related to the diameter at breast height (1.3 m over the ground level), the bole height, the height to the first branch, crown height, the crown diameter, number of branches on each individual tree. In these plots, 143 sheets were used to determine the length of leaf, the pinna length, leaflets’ length, numbers of pinna, the number of leaflets, and the stalk diameter. In addition, 735 cloves were measured to determine the fruit pods’ diameter, pod length, the total fruit weight and number of seeds per fruit, the seed length, the weight of a seed, and pulp weight. Analysis of variance components shows that the variability of Prosopis is generally greater among individuals than within vegetation types and climatic zones. Discriminant analysis showed that of the 19 morphometric characters seven (7) in the vegetation types and twelve (12) in climate zones revealed a statistically significant discriminating pattern r (prob. P. africana trees measured, 10 morphogroups were depicted on the basis of 19 morphometric characteristics (R2 = 52.6%).展开更多
The aim of this research was to investigate the interactions between Prosopis plants and soils in the Kalahari area, south west of Botswana. The underlying assumptions of the research were that Prosopis plants signifi...The aim of this research was to investigate the interactions between Prosopis plants and soils in the Kalahari area, south west of Botswana. The underlying assumptions of the research were that Prosopis plants significantly enhanced the nutrient content and improved the condition of soils in the study area, and that the height and canopy size of Prosopis plants affected the interactions between Prosopis plants and the soils. Firstly, soil samples were collected under 42 randomly selected Prosopis plant canopies and in the spaces between Prosopis plant canopies at the depth of 0 -20 cmand 60 –80 cm. Secondly, soil samples were collected under 45 randomly selected Prosopis plant canopies of three different categories of height and canopy size at the depth of 0 -10 cm. The soil samples were analysed for soil organic carbon, pH, total nitrogen (N), electrical conductivity (EC), calcium (Ca), sodium (Na), potassium (K), and magnesium (Mg). Soil collected under Prosopis plant canopies and in the spaces between Prosopis plant canopies showed statistically significant difference in the soil organic carbon content (F = 2.68, P = 0.05, α = 0.05), pH (F = 44.81, P α = 0.05) and electrical conductivity (EC) (F = 3.75, P = 0.01, α = 0.05). Statistically significant difference was also observed in the comparison of soils existing under Classes 1, 2 and 3 Prosopis plant canopies in relation to pH and EC (F = 6.56, P = 0.01 and F = 4.77, P = 0.01 respectively at α = 0.05). Therefore, it was concluded that the fundamental assumptions of the study were valid.展开更多
Prosopis farcta, a plant belongs to the mimosoideae, is characterized by a very wide spectrum of various bioactive and medical constituents. Vitexin, the marker flavonoid found in Prosopis, has potent and broad antitu...Prosopis farcta, a plant belongs to the mimosoideae, is characterized by a very wide spectrum of various bioactive and medical constituents. Vitexin, the marker flavonoid found in Prosopis, has potent and broad antitumour efficacy in preclinical models. Many studies had been done for the isolation of flavonoids (vitexin) by completely different chromatographically methodology. During this study, vitexin was isolated from Prosopis farcta by 6 different extraction methods in which parameters as the type, concentration and pH of the extracting solvents considered. Among different solvent systems used, methanol-water (40%, containing acetic acid 0.5%) was found to be the best solvent generating the highest yield (0.554 mg·g-1 DW) from Prosopis leaves. The present work suggests an efficient method for estimation the greatest content of vitexin analyzed by HPLC technique and introduces Prosopis farcta as a suitable source of this flavonoid with several pharmacological properties.展开更多
This study investigated the antifungal activity of leaf extracts of Prosopis africana and Anacardium occidentale against Macrophomina phaseolina, the causal agent of root rot of Sesamum indicum L. Phytochemical analys...This study investigated the antifungal activity of leaf extracts of Prosopis africana and Anacardium occidentale against Macrophomina phaseolina, the causal agent of root rot of Sesamum indicum L. Phytochemical analysis of the two plants showed the presence of alkaloids, saponins, tannins, flavonoids and anthraquinones in petroleum ether, ethyl acetate, methanol and water extracts. The effectiveness of the two medicinal plants viz: P. africana and A. occidentale was tested against the causative agent of root rot of Sesamum indicum L. The effect of plant leaf extracts on mycelia growth of the test organism shows that both P. africana and A. anacardium reduced the mycelia growth significantly as compared to the control (plate, 2, 3, 4). The antifungal property of P. africana and A. occidentale makes these plants of potential interest for the control of the fungi Macrophomina phaseolina.展开更多
Prosopis laevigata and Opuntia ficus-indica grow in arid and semiarid regions of Mexico and other countries. Both produce biopolymers with interesting characteristics from the rheological point of view as well as beca...Prosopis laevigata and Opuntia ficus-indica grow in arid and semiarid regions of Mexico and other countries. Both produce biopolymers with interesting characteristics from the rheological point of view as well as because of their coagulating-flocculating capabilities. Prosopis produce galactomannans inside the endosperm, very similar to those found in guar, locust bean, and tara gums. Opuntia sp. produces mucilage that contains polygalacturonic acid and five neutral sugars. Prosopis seed gum has not been proposed to be used as coagulant-flocculant before. In the case of Opuntia mucilage, some authors have suggested its use in the treatment of waters, using either the mucilage or the whole cladode powder. The use of these products in the treatment of municipal or even industrial wastewaters could give rise to diverse benefits. From the environmental point of view, treated waters with neither Fe nor Al, nor synthetic polymers would be obtained (with less toxicity risk). Besides, the produced sludges would be smaller in amount, with better biodegradability, and lower metals content. From the economical point of view, the use of these biopolymers would give an added value to the Opuntia and Prosopis culture in Mexico, helping small communities to enhance their incomes by producing environmental-friendly products. This work shows that both Prosopis galactomannan and Opuntia mucilage can be used to treat municipal wastewaters with an initial organic charge of about 827 mg/L as COD by the coagulation-flocculation process, with COD removals for the mesquite seed gum of up to 90% (pH 10, dose of 75 mg/L) and of 60% (pH 7, doses of 50 and 150 mg/L). In the case of mucilage, 65% of the initial COD was removed at pH 10 (dose of 50 mg/L). These figures are very promising for the treatment of wastewaters, with environmental-friendly products.展开更多
Anatomical features of wood have a great variation among species as a result of genetic and environmental factors. The anatomical heartwood characteristics of Prosopis laevigata species from two areas with differences...Anatomical features of wood have a great variation among species as a result of genetic and environmental factors. The anatomical heartwood characteristics of Prosopis laevigata species from two areas with differences on temperature and rain precipitation on northeast Mexico were compared. Fibers length (μm), diameter of vessels (μm), and the area of the vessels (μm-2) were measured using light microscopy coupled with a digitized-image analysis system. The differences were statistically analyzed with analysis of variance. Statistical differences between fibers length (p 0.0001) and diameter of the vessels (p 0.001) from the two localities were found. The locality Linares, Nuevo León, Mexico, with higher precipitation and lower temperature, showed higher fiber length and higher diameter of the vessels than China, Nuevo León. Hard environmental conditions, where low precipitation values and high temperatures prevail, condition P. laevigata trees do reduce the risk of losing water.展开更多
This study assessed the effects of Prosopis juliflora invasion on livelihood diversification and evaluated the determinants of livelihood diversification in two districts in the South Afar region of Northeast Ethiopia...This study assessed the effects of Prosopis juliflora invasion on livelihood diversification and evaluated the determinants of livelihood diversification in two districts in the South Afar region of Northeast Ethiopia.Using random sampling method,154 households and 2 focus groups composed of 10 individuals were selected from four sites in the two districts.The relationship between P.juliflora invasion and incomes obtained from P.juliflora varied across the study sites.In Awash Fentale District and Amibara District,11.0%and 3.2%of households,respectively,earned income from P.juliflora charcoal production.In total,14.3%of households were involved in charcoal production.In addition,19.9%of households earned income from selling P.juliflora pods and wood materials in the two districts.With the exception of income from P.juliflora charcoal production,the sex of households did not affect incomes from other livelihood activities.Moreover,household educational attainment significantly affected income obtained from vegetables,fruits,and cereal crops.Male householders were engaged in more diverse livelihood activities than female householders.Reversing the severe invasion of P.juliflora on grazing and woodlands in the region is advisable through integrated natural resources,pastoralist participation,and multidisciplinary research strategies.展开更多
Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth performance.Several studies have tested the effect of soil bacterial microbiome on growth...Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth performance.Several studies have tested the effect of soil bacterial microbiome on growth performance of native and invasive plants,but the influence of specific bacterial isolates has not been investigated.Here,we investigated the effects of soil bacterial exclusion by soil sterilization and by inoculation of Streptomyces rhizobacterial isolates on the growth performance of native and invasive Prosopis congeners.Results Plant growth performance of invasive P.juliflora was significantly reduced when grown in sterilized soils,whereas native P.cineraria showed enhanced growth performance in the sterilized soils.When grown in the soil inoculated with the specific Streptomyces isolate from P.juliflora(PJ1),the growth performance of invasive P.juliflora was significantly enhanced while that of native P.cineraria seedlings was significantly reduced.However,inoculation of P.cineraria and P.juliflora seedlings with Streptomyces isolate from the rhizosphere of native P.cineraria(PC1)had no significant effect on the growth performances either of P.juliflora or P.cineraria.Conclusion Our study reveals that invasive P.juliflora experiences positive feedback from the non-native soil bacterial community,while the native P.cineraria experiences negative feedback from its soil bacterial community.Our results provide fresh experimental evidence for the enemy release hypothesis,and further our understanding of the contrasting growth-promoting effects of differentially recruited microbial species belonging to the same genus(Streptomyces)in the rhizospheres of alien invasive and native plants.展开更多
Introduction:An evergreen shrub,Prosopis juliflora is one of the most invasive species in arid and semi-arid areas.Since its introduction to the Middle Awash area of Ethiopia,it has invaded a huge acreage of grass-and...Introduction:An evergreen shrub,Prosopis juliflora is one of the most invasive species in arid and semi-arid areas.Since its introduction to the Middle Awash area of Ethiopia,it has invaded a huge acreage of grass-and rangelands which are life-supporting unit for Afar pastoralists.Methods:Survey,using group discussion and questionnaire,was made to study the effect of P.juliflora invasion on Afar pastoral livelihoods.The obtained data were analyzed using Wilcoxon signed-rank test,chi-square analysis,and logistic regression.Results:According to the result,84%of the total surveyed households rated P.juliflora as undesirable species even though the bush was often used for fuelwood,fencing homesteads,and barn and house construction.Invasion of P.juliflora was also blamed to limit transhumance,occupying settlement areas and affecting multipurpose trees/bushes and grass availability.All these effects put pressure on the livestock assets causing about 80%livestock loss,testing the pastoral livelihoods heavily.Each household,on average,lost 6.5 small stock and 7 cattle during the past 10 years due to health hazards caused by P.juliflora pod.Consequently,P.juliflora as a source of income was considered by a quarter of the surveyed pastoral households,with the age of a household head and change in livestock asset being influential variables in decision-making.Conclusions:In sum,P.juliflora invasion has made livestock rearing extremely difficult which raised pastoralists’ecological vulnerability in the fragile ecosystem they possess.展开更多
Background:Species Distribution Modelling(SDM)coupled with freely available multispectral imagery from Sentinel-2(S2)satellite provides an immense contribution in monitoring invasive species.However,attempts to evalua...Background:Species Distribution Modelling(SDM)coupled with freely available multispectral imagery from Sentinel-2(S2)satellite provides an immense contribution in monitoring invasive species.However,attempts to evaluate the performances of SDMs using S2 spectral bands and S2 Radiometric Indices(S2-RIs)and biophysical variables,in particular,were limited.Hence,this study aimed at evaluating the performance of six commonly used SDMs and one ensemble model for S2-based variables in modelling the current distribution of Prosopis juliflora in the lower Awash River basin,Ethiopia.Thirty-five variables were computed from Sentinel-2B level-2A,and out of the variables,twelve significant variables were selected using Variable Inflation Factor(VIF).A total of 680 presence and absence data were collected to train and validate variables using the tenfold bootstrap replication approach in the R software“sdm”package.The performance of the models was evaluated using sensitivity,specificity,True Skill Statistics(TSS),kappa coefficient,area under the curve(AUC),and correlation.Results:Our findings demonstrated that except bioclim all machine learning and regression models provided successful prediction.Among the tested models,Random Forest(RF)performed better with 93%TSS and 99%AUC followed by Boosted Regression Trees(BRT),ensemble,Generalized Additive Model(GAM),Support Vector Machine(SVM),and Generalized Linear Model(GLM)in decreasing order.The relative influence of vegetation indices was the highest followed by soil indices,biophysical variables,and water indices in decreasing order.According to RF prediction,16.14%(1553.5 km^(2))of the study area was invaded by the alien species.Conclusions:Our results highlighted that S2-RIs and biophysical variables combined with machine learning and regression models have a higher capacity to model invasive species distribution.Besides,the use of machine learning algorithms such as RF algorithm is highly essential for remote sensing-based invasive SDM.展开更多
Woody species within pastures and savannas are often associated with‘resource islands’characterized by higher fertility under canopies trees.The aims of this study were to evaluate(1)the effects of Prosopis juliflor...Woody species within pastures and savannas are often associated with‘resource islands’characterized by higher fertility under canopies trees.The aims of this study were to evaluate(1)the effects of Prosopis juliflora on some soil physicochemical properties and(2)the impacts of Prosopis invasion on soil salinity.For soil physicochemical analysis,a total of 104 soil samples from Teru and Yalo Districts were collected.The soil samples were collected from soil depths of 0-15 cm and 15-30 cm in Prosopis invaded and non-invaded open grazing lands.Invasion of Prosopis had significantly affected soil pH,exchangeable Na^(+),water soluble Ca^(2+)+Mg^(2+),water soluble Na^(+),and exchangeable sodium percentage in Teru and Yalo Districts(p<0.05).The invasion of Prosopis significantly increased soil pH(1.5%),but decreased exchangeable Na^(+)(24.2%),exchangeable sodium percentage(21.6%),and water soluble Ca^(2+)+Mg^(2+)(39.9%)than non-invaded lands.Clay content of Prosopis invaded lands was higher by 19%than non-invaded lands.However,sand content of soil was higher under non-invaded lands by 5.6%than Prosopis invaded lands.Most results indicated that invasion of Prosopis had positive effects on physicochemical properties and thus conducive for cereal crops and forages.展开更多
文摘For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L^-1 and 500 mg·L^-1 and combinational treatment of scarification with gibberellic acid of 250 mg·L^-1 and 500 mg·L^-1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.
文摘Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and biodiversity.To better understand the impacts of biological invasions on soil,we compared topsoil physiochemical properties at sites with invasive alien tree species(Prosopis juliflora),native tree species(Prosopis cineraria,Acacia tortilis,and Acacia ehrenbergiana),and mixed tree species in Hormozgan Province of Iran in May 2018.In this study,we collected 40 soil samples at a depth of 10 cm under single tree species,including P.juliflora,P.cineraria,A.tortilis,and A.ehrenbergiana,as well as under mixed tree species.The results showed that organic matter,moisture,potassium,calcium,nitrogen,and magnesium in topsoil at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria were higher than that at sites where P.juliflora was present(P<0.05).Sodium at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria and P.juliflora was lower as compared to that at sites with just A.tortilis and A.ehrenbergiana.Electrical conductivity was lower at sites with A.tortilis and A.ehrenbergiana growing in combination with P.cineraria,and it was higher at sites with mixed Acacia and P.juliflora trees.Based on the generally more positive effect of native Acacia and P.cineraria on topsoil physiochemical properties as compared to the P.julifora,afforestation with native tree species is preferable for soil restoration.In addition,due to the negative effects of P.julifora on soil properties,P.julifora spread should be better managed.
基金supported by the Core Research Grant of SERB–DST,New Delhi,Government of India。
文摘This study investigates the potential of native biocontrol agents(BCAs)as controls against Ganoderma lucidum causing root rot mortality in Indian mesquite.The disease is prevalent in sandy soils where trees grow under rainfed conditions.In addition,a beetle namely A canthophorus serraticornis damages the roots,resulting in increasing vulnerability of the host thereby allowing easy of the pathogen.In dual culture tests,Ganoderma infected cowpea root bit experiment and compatibility with insecticides revealed that the three BCAs(Trichoderma longibrachiatum,T.harzianum,and Aspergillus nidulans)significantly inhibited G.lucidum mycelial growth.The highest mycelial growth inhibition(47.6%)was recorded after 96 h followed by 39.8%and 29.3%at 72 and 48 h,respectively,by T.longibrachium.Cell free filtrates of T.longibrachiatum,T.harzianum,and A.nidulans were superior in inhibiting mycelium growth.A low concentration(3 ml)of T.longibrachiatum was more effective in inhibiting mycelium growth compared to other BCAs.Both P rosopis julifl ora compost and onion residue compost amendments as food substrates favored the growth of these BCAs,which ultimately reduced the viability of Ganoderma-colonized root bits of cowpea.Studies on compatibility between insecticides and BCAs suggests that T.longibrachiatum,harzianum and A.nidulans can be combined with phorate or chloropyriphos(both organophosphates)at variable concentrations if amended together for partially infected trees,or as a prophylactic measure in healthy trees.These studies demonstrate that there is considerable opportunity for using native BCAs against G.lucidum in managing root rot disease.
文摘Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of the compounds by standard chromatographic techniques.With the help of DART-MS,chemical fingerprint of raw plant parts were generated,which revealed the presence of piperidine alkaloids in leaf,pod and flower.A comparative study of the distribution pattern,showed variation in the presence and distribution of these alkaloids in various parts of P.juliflora.The leaves and pod displayed the largest alkaloid pattern with a total of 12 different alkaloids in each part,whereas only 4 alkaloids were present in flower.Alkaloids:julifloridine,prosopine,prosopinine and prosafrinine were ubiquitously distributed in all the alkaloid rich plant parts.Juliprosopine was pre-eminet alkaloid in leaf,whereas pod and flower displayed copious amounts of julifloridine.
文摘This study was aimed to determine the extent to which Prosopis species had invaded four settlements (Bokspits, Rappelspan, Vaalhoek and Struizendam) located in the Kgalagadi Desert south west of Botswana, investigate the perceptions of the communities about the existence of the species in their environment and assess possible control options for the spread of Prosopis plants in the area. Prosopis plants were sampled in 42 quadrats of 625 m2 along a 70 km Prosopis invasion gradient from Struizendam to Rappelspan. Using the Global Positioning System (GPS), the locations of all quadrats were established. The distribution map of Prosopis plants was produced using ArcGIS 9.2 (ESRI Inc.). Questionnaire survey and focused group discussions were used to collect data on the perceptions of rural communities about the species. A total of 342 respondents comprising 139 males and 203 females were interviewed, and four focussed group discussions were conducted. The results indicated that the invasion of Prosopis species was prominent in and around settlements suggesting that anthropogenic activities had a significant role in the spread of Prosopis plants in the area. The perceptions of rural communities about Prosopis plants appeared to be moulded by the impacts of the plants on their livelihoods as well as their micro-economic status. The respondents (71.30%) expressed the view that the invasion of Prosopis species negatively affected the livelihoods of the communities in the study area. They identified eradication as the preferred method of controlling the spread of Prosopis plants. On the contrary, this study recommended the integrated environmental management paradigm as the best options for the control of the spread of Prosopis plants in the area.
基金supported by“The chica,the retamo,and the algarrobo:umbrella species for the conservation of the Native Forest of the Ischigualasto Provincial Park and nearby zones.Biological interactions,effects of human activities and their mitigation”,Plan for the Conservation of Native Forests Law 26.331.
文摘Background:Trees and forests in drylands help mitigate the challenges through provision of economic products and vital environmental services such as habitat for biodiversity,prevention of erosion and desertification,regulation of water,microclimate,and soil fertility.The condition and changes in dry forests can be assessed by using ecological indicators able to quantify spatial and temporal changes in vegetation.One of the ways to determine the condition of the forest is to study the dominant tree species and its regeneration.Our study aimed to assess whether the abundance of Prosopis flexuosa saplings is affected by environmental and biological factors.Results:To evaluate the first variables we used data from remote sensing such as satellite images and Aster Global Digital Model(GDEM).The second set of variables was about exotic and native ungulates and we used feces of these animals and camera traps to take data.We found that sapling abundance related positively to sandy substrates and negatively to Wetness Index.On the other hand,in relation to biological variables,the abundance of saplings was positively affected by density of adult trees and by number of seeds dispersed by equines,but space use by Lama guanicoe had a negative relationship with saplings.This research shows that P.flexuosa saplings are benefited from sandy substrates and the conditions around adult trees.In addition to this,we found that exotic ungulates in low densities have neutral(i.e.cattle)or positive(i.e.equines)effects on sapling abundance.Conclusions:Based on these findings,we conclude that regeneration of the population of P.flexuosa in our study area has no major problems.In addition,we corroborated that the presence of exotic and domestic ungulates in low densities does not have deleterious consequences for saplings of the dominant tree,P.flexuosa.
文摘Background:Investigating new therapies for inflammatory bowel disease among natural products has recently been gaining attention.Although Prosopis farcta has repeatedly been mentioned in traditional Persian medicine as a therapeutic option for inflammatory bowel disease,no evidence-based investigations have been conducted on this topic.The aim of this study was to assess the impact of P.farcta on acetic acid-induced colitis in rats.Methods:A hydroalcoholic extract of P.farcta fruits was prepared.Thirty-six adult Wistar rats were divided into six groups,and colitis was induced in five groups,except the sham group,using acetic acid solution.The animals received distinctive daily doses of P.farcta(50,75,and 100 mg/kg/day,p.o.)and dexamethasone(1 mg/kg/day,i.p.)as standard treatment for two progressive days,starting from colitis induction.Microscopic and histopathological examinations were performed on inflamed colonic tissue.Tissue concentrations of interleukin-1βand tumor necrosis factor-αwere assessed using enzyme-linked immunosorbent assay kits.To identify the role of oxidative stress in ulcerative colitis,the levels of malondialdehyde and myeloperoxidase were measured in colon tissues.Results:Treatment with all concentrations of P.farcta attenuated inflammation and ulcers compared with saline treatment in the control group(P<0.01 for 50 mg/kg;P<0.001 for 75 and 100 mg/kg/day).The best suppression of tumor necrosis factor-αand interleukin-1βwas observed at a dose of 100 mg/kg P.farcta(P<0.001).This dose showed the best effect in reducing myeloperoxidase and malondialdehyde in ulcerative colitis-induced rats(P<0.001).Conclusion:P.farcta can be considered a promising candidate for treating ulcerative colitis;thus,it requires further confirmation by clinical trials.
文摘Arbuscular mycorrhizal (AM) fungi associated with Prosopis cineraria (Khejri) were assessed for their qualitative and quantitative distribution from eight districts of Rajasthan. A total of three species of Acaulospora, one species of Entrophospora, two species of Gigaspora, twenty-one species of Glomus, seven species of Sclerocystis and three species of Scutellospora were recorded. A high diversity of AM fungi was observed and it varied at different study sites. Among these six genera, Glomus occurred most frequently. Glomus fasciculatum, Glomus aggregatum, and Glomus mosseae were found to be the most predominant AM fungi in infecting Prosopis cineraria. Acaulospora, G. fasciculatum, Sclerocystis was found in all the fields studied, while Scutellospora species were found only in few sites. A maximum of thirty-six AM fungal species were isolated and identified from Jodhpur, whereas only thirteen species were found from Jaisalmer. Spores of Glomusfasciculatum were found to be most abundant under Prosopis cineraria.
文摘An experiment was initiated in 2008 to evaluate the impact of irrigation regimes on germination and growth patterns of seedlings of Prosopis cineraria in the arid areas of Thar, India. Seeds collected from dried pods of P cineraria were sown in polybags placed in nursery beds. Different irrigation regimes were provided to different beds and data regarding germination and growth were recorded to study natural regeneration. The study revealed that irrigation regimes significantly affected the germination and growth of P cineraria under nursery conditions. The germination rate declined as the irrigation regime shifted from a daily to a fortnightly ba- sis. Height of the seedlings also declined with a decrease in the intensity of irrigation. Thus, it can be concluded that germination and growth of seedlings of P cineraria under nursery conditions can be enhanced by providing irrigation at regular intervals.
文摘The morphological variability of Prosopis africana in its natural range (which includes three climate zones: Guinean zone, Sudano-Guinean zone and Sudanese zone) of Benin was studied on the basis of forest inventory carried out in three different vegetation types (savannah, fallow and field). The data recorded in 139 plots of 1000 m2 each related to the diameter at breast height (1.3 m over the ground level), the bole height, the height to the first branch, crown height, the crown diameter, number of branches on each individual tree. In these plots, 143 sheets were used to determine the length of leaf, the pinna length, leaflets’ length, numbers of pinna, the number of leaflets, and the stalk diameter. In addition, 735 cloves were measured to determine the fruit pods’ diameter, pod length, the total fruit weight and number of seeds per fruit, the seed length, the weight of a seed, and pulp weight. Analysis of variance components shows that the variability of Prosopis is generally greater among individuals than within vegetation types and climatic zones. Discriminant analysis showed that of the 19 morphometric characters seven (7) in the vegetation types and twelve (12) in climate zones revealed a statistically significant discriminating pattern r (prob. P. africana trees measured, 10 morphogroups were depicted on the basis of 19 morphometric characteristics (R2 = 52.6%).
文摘The aim of this research was to investigate the interactions between Prosopis plants and soils in the Kalahari area, south west of Botswana. The underlying assumptions of the research were that Prosopis plants significantly enhanced the nutrient content and improved the condition of soils in the study area, and that the height and canopy size of Prosopis plants affected the interactions between Prosopis plants and the soils. Firstly, soil samples were collected under 42 randomly selected Prosopis plant canopies and in the spaces between Prosopis plant canopies at the depth of 0 -20 cmand 60 –80 cm. Secondly, soil samples were collected under 45 randomly selected Prosopis plant canopies of three different categories of height and canopy size at the depth of 0 -10 cm. The soil samples were analysed for soil organic carbon, pH, total nitrogen (N), electrical conductivity (EC), calcium (Ca), sodium (Na), potassium (K), and magnesium (Mg). Soil collected under Prosopis plant canopies and in the spaces between Prosopis plant canopies showed statistically significant difference in the soil organic carbon content (F = 2.68, P = 0.05, α = 0.05), pH (F = 44.81, P α = 0.05) and electrical conductivity (EC) (F = 3.75, P = 0.01, α = 0.05). Statistically significant difference was also observed in the comparison of soils existing under Classes 1, 2 and 3 Prosopis plant canopies in relation to pH and EC (F = 6.56, P = 0.01 and F = 4.77, P = 0.01 respectively at α = 0.05). Therefore, it was concluded that the fundamental assumptions of the study were valid.
文摘Prosopis farcta, a plant belongs to the mimosoideae, is characterized by a very wide spectrum of various bioactive and medical constituents. Vitexin, the marker flavonoid found in Prosopis, has potent and broad antitumour efficacy in preclinical models. Many studies had been done for the isolation of flavonoids (vitexin) by completely different chromatographically methodology. During this study, vitexin was isolated from Prosopis farcta by 6 different extraction methods in which parameters as the type, concentration and pH of the extracting solvents considered. Among different solvent systems used, methanol-water (40%, containing acetic acid 0.5%) was found to be the best solvent generating the highest yield (0.554 mg·g-1 DW) from Prosopis leaves. The present work suggests an efficient method for estimation the greatest content of vitexin analyzed by HPLC technique and introduces Prosopis farcta as a suitable source of this flavonoid with several pharmacological properties.
文摘This study investigated the antifungal activity of leaf extracts of Prosopis africana and Anacardium occidentale against Macrophomina phaseolina, the causal agent of root rot of Sesamum indicum L. Phytochemical analysis of the two plants showed the presence of alkaloids, saponins, tannins, flavonoids and anthraquinones in petroleum ether, ethyl acetate, methanol and water extracts. The effectiveness of the two medicinal plants viz: P. africana and A. occidentale was tested against the causative agent of root rot of Sesamum indicum L. The effect of plant leaf extracts on mycelia growth of the test organism shows that both P. africana and A. anacardium reduced the mycelia growth significantly as compared to the control (plate, 2, 3, 4). The antifungal property of P. africana and A. occidentale makes these plants of potential interest for the control of the fungi Macrophomina phaseolina.
文摘Prosopis laevigata and Opuntia ficus-indica grow in arid and semiarid regions of Mexico and other countries. Both produce biopolymers with interesting characteristics from the rheological point of view as well as because of their coagulating-flocculating capabilities. Prosopis produce galactomannans inside the endosperm, very similar to those found in guar, locust bean, and tara gums. Opuntia sp. produces mucilage that contains polygalacturonic acid and five neutral sugars. Prosopis seed gum has not been proposed to be used as coagulant-flocculant before. In the case of Opuntia mucilage, some authors have suggested its use in the treatment of waters, using either the mucilage or the whole cladode powder. The use of these products in the treatment of municipal or even industrial wastewaters could give rise to diverse benefits. From the environmental point of view, treated waters with neither Fe nor Al, nor synthetic polymers would be obtained (with less toxicity risk). Besides, the produced sludges would be smaller in amount, with better biodegradability, and lower metals content. From the economical point of view, the use of these biopolymers would give an added value to the Opuntia and Prosopis culture in Mexico, helping small communities to enhance their incomes by producing environmental-friendly products. This work shows that both Prosopis galactomannan and Opuntia mucilage can be used to treat municipal wastewaters with an initial organic charge of about 827 mg/L as COD by the coagulation-flocculation process, with COD removals for the mesquite seed gum of up to 90% (pH 10, dose of 75 mg/L) and of 60% (pH 7, doses of 50 and 150 mg/L). In the case of mucilage, 65% of the initial COD was removed at pH 10 (dose of 50 mg/L). These figures are very promising for the treatment of wastewaters, with environmental-friendly products.
文摘Anatomical features of wood have a great variation among species as a result of genetic and environmental factors. The anatomical heartwood characteristics of Prosopis laevigata species from two areas with differences on temperature and rain precipitation on northeast Mexico were compared. Fibers length (μm), diameter of vessels (μm), and the area of the vessels (μm-2) were measured using light microscopy coupled with a digitized-image analysis system. The differences were statistically analyzed with analysis of variance. Statistical differences between fibers length (p 0.0001) and diameter of the vessels (p 0.001) from the two localities were found. The locality Linares, Nuevo León, Mexico, with higher precipitation and lower temperature, showed higher fiber length and higher diameter of the vessels than China, Nuevo León. Hard environmental conditions, where low precipitation values and high temperatures prevail, condition P. laevigata trees do reduce the risk of losing water.
文摘This study assessed the effects of Prosopis juliflora invasion on livelihood diversification and evaluated the determinants of livelihood diversification in two districts in the South Afar region of Northeast Ethiopia.Using random sampling method,154 households and 2 focus groups composed of 10 individuals were selected from four sites in the two districts.The relationship between P.juliflora invasion and incomes obtained from P.juliflora varied across the study sites.In Awash Fentale District and Amibara District,11.0%and 3.2%of households,respectively,earned income from P.juliflora charcoal production.In total,14.3%of households were involved in charcoal production.In addition,19.9%of households earned income from selling P.juliflora pods and wood materials in the two districts.With the exception of income from P.juliflora charcoal production,the sex of households did not affect incomes from other livelihood activities.Moreover,household educational attainment significantly affected income obtained from vegetables,fruits,and cereal crops.Male householders were engaged in more diverse livelihood activities than female householders.Reversing the severe invasion of P.juliflora on grazing and woodlands in the region is advisable through integrated natural resources,pastoralist participation,and multidisciplinary research strategies.
基金supported by Faculty Research Grant of the Institution of Eminence,University of Delhi provided to MKPThis work received grant specifically from Department of Biotechnology(DBT/2015/UOD/358),Government of India,provided to RK+2 种基金Financial support received from Council for Scientific and Industrial Research(CSIR)(09/045(1601)/2018/EMR-I)provided to MS is acknowledgedInfrastructure facilities funded by DST-FIST,UGC-SAP(DRS)and TEQIP and AICTE-MODROBS are acknowledgedThe financial assistance of IoE FRP Grant to MKP is gratefully acknowledged.
文摘Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth performance.Several studies have tested the effect of soil bacterial microbiome on growth performance of native and invasive plants,but the influence of specific bacterial isolates has not been investigated.Here,we investigated the effects of soil bacterial exclusion by soil sterilization and by inoculation of Streptomyces rhizobacterial isolates on the growth performance of native and invasive Prosopis congeners.Results Plant growth performance of invasive P.juliflora was significantly reduced when grown in sterilized soils,whereas native P.cineraria showed enhanced growth performance in the sterilized soils.When grown in the soil inoculated with the specific Streptomyces isolate from P.juliflora(PJ1),the growth performance of invasive P.juliflora was significantly enhanced while that of native P.cineraria seedlings was significantly reduced.However,inoculation of P.cineraria and P.juliflora seedlings with Streptomyces isolate from the rhizosphere of native P.cineraria(PC1)had no significant effect on the growth performances either of P.juliflora or P.cineraria.Conclusion Our study reveals that invasive P.juliflora experiences positive feedback from the non-native soil bacterial community,while the native P.cineraria experiences negative feedback from its soil bacterial community.Our results provide fresh experimental evidence for the enemy release hypothesis,and further our understanding of the contrasting growth-promoting effects of differentially recruited microbial species belonging to the same genus(Streptomyces)in the rhizospheres of alien invasive and native plants.
文摘Introduction:An evergreen shrub,Prosopis juliflora is one of the most invasive species in arid and semi-arid areas.Since its introduction to the Middle Awash area of Ethiopia,it has invaded a huge acreage of grass-and rangelands which are life-supporting unit for Afar pastoralists.Methods:Survey,using group discussion and questionnaire,was made to study the effect of P.juliflora invasion on Afar pastoral livelihoods.The obtained data were analyzed using Wilcoxon signed-rank test,chi-square analysis,and logistic regression.Results:According to the result,84%of the total surveyed households rated P.juliflora as undesirable species even though the bush was often used for fuelwood,fencing homesteads,and barn and house construction.Invasion of P.juliflora was also blamed to limit transhumance,occupying settlement areas and affecting multipurpose trees/bushes and grass availability.All these effects put pressure on the livestock assets causing about 80%livestock loss,testing the pastoral livelihoods heavily.Each household,on average,lost 6.5 small stock and 7 cattle during the past 10 years due to health hazards caused by P.juliflora pod.Consequently,P.juliflora as a source of income was considered by a quarter of the surveyed pastoral households,with the age of a household head and change in livestock asset being influential variables in decision-making.Conclusions:In sum,P.juliflora invasion has made livestock rearing extremely difficult which raised pastoralists’ecological vulnerability in the fragile ecosystem they possess.
文摘Background:Species Distribution Modelling(SDM)coupled with freely available multispectral imagery from Sentinel-2(S2)satellite provides an immense contribution in monitoring invasive species.However,attempts to evaluate the performances of SDMs using S2 spectral bands and S2 Radiometric Indices(S2-RIs)and biophysical variables,in particular,were limited.Hence,this study aimed at evaluating the performance of six commonly used SDMs and one ensemble model for S2-based variables in modelling the current distribution of Prosopis juliflora in the lower Awash River basin,Ethiopia.Thirty-five variables were computed from Sentinel-2B level-2A,and out of the variables,twelve significant variables were selected using Variable Inflation Factor(VIF).A total of 680 presence and absence data were collected to train and validate variables using the tenfold bootstrap replication approach in the R software“sdm”package.The performance of the models was evaluated using sensitivity,specificity,True Skill Statistics(TSS),kappa coefficient,area under the curve(AUC),and correlation.Results:Our findings demonstrated that except bioclim all machine learning and regression models provided successful prediction.Among the tested models,Random Forest(RF)performed better with 93%TSS and 99%AUC followed by Boosted Regression Trees(BRT),ensemble,Generalized Additive Model(GAM),Support Vector Machine(SVM),and Generalized Linear Model(GLM)in decreasing order.The relative influence of vegetation indices was the highest followed by soil indices,biophysical variables,and water indices in decreasing order.According to RF prediction,16.14%(1553.5 km^(2))of the study area was invaded by the alien species.Conclusions:Our results highlighted that S2-RIs and biophysical variables combined with machine learning and regression models have a higher capacity to model invasive species distribution.Besides,the use of machine learning algorithms such as RF algorithm is highly essential for remote sensing-based invasive SDM.
文摘Woody species within pastures and savannas are often associated with‘resource islands’characterized by higher fertility under canopies trees.The aims of this study were to evaluate(1)the effects of Prosopis juliflora on some soil physicochemical properties and(2)the impacts of Prosopis invasion on soil salinity.For soil physicochemical analysis,a total of 104 soil samples from Teru and Yalo Districts were collected.The soil samples were collected from soil depths of 0-15 cm and 15-30 cm in Prosopis invaded and non-invaded open grazing lands.Invasion of Prosopis had significantly affected soil pH,exchangeable Na^(+),water soluble Ca^(2+)+Mg^(2+),water soluble Na^(+),and exchangeable sodium percentage in Teru and Yalo Districts(p<0.05).The invasion of Prosopis significantly increased soil pH(1.5%),but decreased exchangeable Na^(+)(24.2%),exchangeable sodium percentage(21.6%),and water soluble Ca^(2+)+Mg^(2+)(39.9%)than non-invaded lands.Clay content of Prosopis invaded lands was higher by 19%than non-invaded lands.However,sand content of soil was higher under non-invaded lands by 5.6%than Prosopis invaded lands.Most results indicated that invasion of Prosopis had positive effects on physicochemical properties and thus conducive for cereal crops and forages.