Farmers’contract breach behavior is cited as one of the major stumbling blocks in the sustainable expansion of contract farming in many developing countries.This paper examines farmers’contract breach decisions from...Farmers’contract breach behavior is cited as one of the major stumbling blocks in the sustainable expansion of contract farming in many developing countries.This paper examines farmers’contract breach decisions from the perspective of time preferences.The empirical analysis is based on a household survey and economic field experiments of poultry households participating in contract farming conducted in Jiangsu Province,China.A discounted utility model and a maximum likelihood technique are applied to estimate farmers’time preferences and the effect of time preferences on contract breach in the production and sales phases are explored with a bivariate probit model.The results show that,on average,the poultry farmers in the sample are generally present biased and impatient regarding future utility.The regression results show that farmers with a higher preference for the present and a higher discount rate are more likely to breach contracts,and time preferences play a greater role in the production phase than in the sales phase.When considering heterogeneity,specific investments and transaction costs promote contract stability only for farmers with a low degree of impatience.Moreover,compared with large-scale farmers,small-scale farmers’contract breach decisions are more significantly affected by their time preferences.These results have implications for contract stability policies and other issues that are impacted by the linking of behavioral preferences to agricultural decisions.展开更多
Agricultural investment project selection is a complex multi-criteria decision-making problem,as agricultural projects are easily influenced by various risk factors,and the evaluation information provided by decisionm...Agricultural investment project selection is a complex multi-criteria decision-making problem,as agricultural projects are easily influenced by various risk factors,and the evaluation information provided by decisionmakers usually involves uncertainty and inconsistency.Existing literature primarily employed direct preference elicitation methods to address such issues,necessitating a great cognitive effort on the part of decision-makers during evaluation,specifically,determining the weights of criteria.In this study,we propose an indirect preference elicitation method,known as a preference disaggregation method,to learn decision-maker preference models fromdecision examples.To enhance evaluation ease,decision-makers merely need to compare pairs of alternatives with which they are familiar,also known as reference alternatives.Probabilistic linguistic preference relations are employed to account for the presence of incomplete and uncertain information in such pairwise comparisons.To address the inconsistency among a group of decision-makers,we develop a pair of 0-1mixed integer programming models that consider both the semantics of linguistic terms and the belief degrees of decision-makers.Finally,we conduct a case study and comparative analysis.Results reveal the effectiveness of the proposed model in solving agricultural investment project selection problems with uncertain and inconsistent decision information.展开更多
Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sol...Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sold to bring in some income. Timely decisions on farm practices such as farm preparation and planting are critical determinants of the seasonal outcomes. In Kenya, most small-scale farmers have no reliable source of information that would help them make timely and accurate decisions. County governments have extension officers who are mandated with giving farmers advisory services to farmers but they are not able to reach most farmers due to facilitation constraints. The mode and format of sharing information is also critical since it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess access to geospatial derived and other crop production information by farmers in four selected counties of Kenya. Specific objectives were to determine the profile of small-scale farmers in terms of age, education and farm size;to determine the type of information that is made available to them by County and Sub-County extension officers including the format and mode of provision;and to determine if the information provided was useful in terms of accuracy, timeliness and adequacy. The results indicated that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary education (34%) or secondary education (29%) and most farmers in all the counties grew maize (71%). Notably, fellow farmers were a source of information (71%) with the frequency of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indicating that they faced challenges while using provided information. The results from the study are insightful and helpful in determining effective ways of providing farmers with useful information to ensure maximum benefits.展开更多
The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been conside...The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been considered as a feasible scheme.However,how to efficiently utilize the limited caching resources to cache diverse contents has been confirmed as a tough problem in the past decade.In this paper,considering the time-varying user requests and the heterogeneous content sizes,a user preference aware hierarchical cooperative caching strategy in edge-user caching architecture is proposed.We divide the caching strategy into three phases,that is,the content placement,the content delivery and the content update.In the content placement phase,a cooperative content placement algorithm for local content popularity is designed to cache contents proactively.In the content delivery phase,a cooperative delivery algorithm is proposed to deliver the cached contents.In the content update phase,a content update algorithm is proposed according to the popularity of the contents.Finally,the proposed caching strategy is validated using the MovieLens dataset,and the results reveal that the proposed strategy improves the delay performance by at least 35.3%compared with the other three benchmark strategies.展开更多
Introduction: Pesticides are currently an essential component of agricultural production techniques for controlling pests and weeds. In Burkina Faso, non-compliance with good practice in the use of pesticides poses a ...Introduction: Pesticides are currently an essential component of agricultural production techniques for controlling pests and weeds. In Burkina Faso, non-compliance with good practice in the use of pesticides poses a real health problem for the population. This study examines the health risks associated with pesticide management in rice-growing areas. Material and Methods: A field survey was conducted in Bama, involving farmers, focusing on their socio-demographic characteristics, pesticide usage, and health effects. Cholinesterase levels were measured in subsample of farmers using a portable device. Data were analysed using Microsoft Excel, calculating means and percentages for various practices. Health consultations, protection methods, and pesticide management were studied. Erythrocyte acetylcholinesterase activity was compared before and after treatment. Data were categorised into classes based on inhibition levels, and correlation analyses determined relationships between variables such as age, years of experience, and cholinesterase activity. Results: The results indicate that rice cultivation is mainly carried out by a fairly young population, with nearly 63% being under the age of 50. Common poor practices in pesticide use include improper storage and reuse of leftover pesticides. Seven types of pesticides were identified, including organophosphates such as glyphosate, which was used in 26.7% of cases. This organophosphate has resulted in class B poisoning, causing a 30% - 50% reduction in erythrocyte cholinesterase activity. The health effects of pesticide use are felt by agricultural farmers through various symptoms of poisoning. Conclusion: To reduce the occurrence of pesticide poisoning, it is essential to launch information and awareness campaigns among the population and farmers to promote safe practices in pesticide use in Bama, Burkina Faso.展开更多
A deep learning access controlmodel based on user preferences is proposed to address the issue of personal privacy leakage in social networks.Firstly,socialusers andsocialdata entities are extractedfromthe social netw...A deep learning access controlmodel based on user preferences is proposed to address the issue of personal privacy leakage in social networks.Firstly,socialusers andsocialdata entities are extractedfromthe social networkandused to construct homogeneous and heterogeneous graphs.Secondly,a graph neural networkmodel is designed based on user daily social behavior and daily social data to simulate the dissemination and changes of user social preferences and user personal preferences in the social network.Then,high-order neighbor nodes,hidden neighbor nodes,displayed neighbor nodes,and social data nodes are used to update user nodes to expand the depth and breadth of user preferences.Finally,a multi-layer attention network is used to classify user nodes in the homogeneous graph into two classes:allow access and deny access.The fine-grained access control problem in social networks is transformed into a node classification problem in a graph neural network.The model is validated using a dataset and compared with other methods without losing generality.The model improved accuracy by 2.18%compared to the baseline method GraphSAGE,and improved F1 score by 1.45%compared to the baseline method,verifying the effectiveness of the model.展开更多
Introduction: Females with sickle cell disease (SCD), despite having a delayed pubertal development, are subject to many worries relating to their abilities to conceive, their capacity to maintain a maternofetal-risk-...Introduction: Females with sickle cell disease (SCD), despite having a delayed pubertal development, are subject to many worries relating to their abilities to conceive, their capacity to maintain a maternofetal-risk-free pregnancy till term and give birth to healthy children without sickle cell disease. Knowing that unplanned pregnancies are more likely to increase maternofetal morbidity and mortality, we sought out to explore the pregnancy preferences in female patients with sickle cell disease to promote healthy conception and childbirth in this vulnerable population. Methodology: We conducted a cross-sectional study involving female patients of child-bearing age with sickle cell disease followed at Laquintinie Hospital Douala or who were members of a local sickle cell association. Pregnancy preferences were determined using the Desire to Avoid Pregnancy (DAP) scale. Factors associated with pregnancy preferences were determined using multivariable linear regression model. Threshold for significance was set at p Results: Seventy-seven patients were included with a mean age of 24.71 ± 5.53 years. Forty patients (51.95%) had one sexual partner and thirteen women (32.5%) used contraceptive methods. Most patients (46.0%) responded “Strongly Agree” or “Agree” to the statement “it would be a good thing for me if I became pregnant in the next 3 months”. The mean DAP score was 1.63 ± 0.91 [1.28 ± 0.82 in those who had a sexual partner and 1.99 ± 0.86 in those who had no sexual partner]. Factors that were positively associated with DAP score were students (b = 0.32, 95% CI [0.21, 0.95], p = 0.003), monthly income ≥ 100,000 FCFA (b = 0.24, 95% CI [0.07, 0.81], p = 0.022), and not having a sexual partner (b = 0.26, 95% CI [0.11, 0.85], p = 0.012). Conclusion: Most female patients with SCD have a low desire to avoid pregnancy. This is especially true for patients who are not students, have a partner and have a low monthly income.展开更多
When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific...When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of Maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations.展开更多
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection...Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.展开更多
This research delves into the hurdles and strategies aimed at augmenting the market involvement of smallholder carrot farmers in Nakuru County, Kenya. Employing a Multinomial Logit (MNL) model, it scrutinizes the fact...This research delves into the hurdles and strategies aimed at augmenting the market involvement of smallholder carrot farmers in Nakuru County, Kenya. Employing a Multinomial Logit (MNL) model, it scrutinizes the factors influencing the selection of marketing outlets among carrot farmers. The findings unveil that a significant majority (81%) of surveyed farmers actively participate in diverse market outlets, encompassing the farm gate, cleaning point, local market, external market, and export market. Notably, pivotal buyers include aggregators, brokers, wholesalers, retailers, and consumers, with transactions predominantly occurring at the farm level. Additionally, the analysis discerns substantial influences of socio-economic characteristics, experiential factors, and geographical proximity on farmers’ choices of market outlets. Specifically, gender, age, land size, farming experience, and distance to markets emerge as critical determinants. Moreover, the study delves into the examination of market margins along the carrot value chain, shedding light on the potential profitability of carrot farming in the region. Remarkably, higher average gross margins are identified in export and external markets, signaling lucrative prospects for farmers targeting these segments. However, disparities in profit distribution between farmers and traders underscore the necessity for interventions to ensure equitable value distribution throughout the value chain. These findings underscore the imperative for tailored interventions to tackle challenges and foster inclusive agricultural development. Strategies such as farmer organizations, contracting, and vertical integration are advocated to enhance market access and profitability for smallholder carrot farmers. Thus, this study enriches our comprehension of the dynamics within carrot value chains and provides valuable insights for policymakers and development practitioners aiming to uplift rural livelihoods and bolster food security.展开更多
BACKGROUND Primary thumb carpometacarpal(CMC)osteoarthritis is one of the most common conditions encountered by hand surgeons.Of the vast number of operations that have been proposed,none have demonstrated results sig...BACKGROUND Primary thumb carpometacarpal(CMC)osteoarthritis is one of the most common conditions encountered by hand surgeons.Of the vast number of operations that have been proposed,none have demonstrated results significantly superior to trapeziectomy alone.AIM The purpose of our study was to determine why surgeons opt for their technique in treating CMC arthritis.METHODS A cross-sectional survey of active members of the American Society for Surgery of the Hand was conducted to evaluate the reasons behind their preferred technique in the treatment of isolated thumb CMC arthritis.Surgeons were contacted by email once and provided with a link to a de-identified survey consisting of 5 treatment questions and 5 demographic questions.RESULTS Of 950 responses were received.40.5%of surgeons preferred trapeziectomy+ligament reconstruction tendon interposition(LRTI),followed by trapeziectomy+suspensionplasty(28.2%),suture button suspension(5.9%),trapeziectomy alone(4.6%),prosthetic arthroplasty(3.2%),arthrodesis(1.1%),and other(6.6%).Proponents of trapeziectomy+LRTI cited familiarity(73.2%),exposure during fellowship(48.8%)and less proximal migration(60%)to be the main reasons affecting their decision.Surgeons who preferred trapeziectomy+suspensionplasty most reported simplicity(74.9%),fewer complications(45.3%),less proximal migration(43.8%),and avoidance of autogenous tissue harvest(42.7%).Advocates of suture button suspension cited avoidance of autogenous tissue harvest(80.4%),shorter immobilization(76.8%),and quicker recovery(73.2%)with their technique.Advocates of trapeziectomy alone cited simplicity(97.7%),fewer complications(86.4%),and avoidance of autogenous tissue harvest(59.1%).In their comments,45%of surgeons choosing trapeziectomy alone cited evidence as an additional rationale.Advocates of prosthetic arthroplasty cited improved pinch strength(83.3%)and improved range of motion(63.3%),while those preferring arthrodesis cited better pinch strength(90%)and frequently in their comments,durability.Of the surgeons who preferred a technique other than LRTI,41.8%reported they had tried LRTI in the past,citing complexity of the procedure,flexor carpi radialis harvest,and longer operative time as reasons for moving on.CONCLUSION Our study provides an update on current treatment trends and offers new insight into the reasons behind surgeons'decision making in the management of thumb carpometacarpal osteoarthritis.Despite strong Level 1 evidence supporting the use of trapeziectomy alone,our findings demonstrate that most surgeons continue to supplement trapeziectomy with other techniques such as LRTI or suspensionplasty.Several factors including familiarity,personal experience(Level 4 evidence),and comfort may be more influential than Level 1 evidence in determining the techniques in a surgeon's armamentarium.Further prospective studies are needed to determine the optimal technique for surgical management of Eaton stages II-IV CMC arthritis and how these studies will affect surgeons’choice.展开更多
The cattle production in Romeas Haek district,Svay Rieng province,was developed remarkably,since there were some households raising cattle in large number,more than 20 heads.The grazing method of cattle was tethering ...The cattle production in Romeas Haek district,Svay Rieng province,was developed remarkably,since there were some households raising cattle in large number,more than 20 heads.The grazing method of cattle was tethering and free grassing in the commune grass,since the natural grass and rice straw were the main source of cattle feed,however some of them supplemented their cattle with crop-byproducts,planting grass or concentrated feed.For the majority,BCS(Body Condition Scoring)of the cattle in those areas was 3 accounting for 52%-73.33%,but it was found the thin cattle has low BCS of 2 accounting for 11.11%to 40.00%and also fat cattle has BCS of 4 up to 27.78%.However,the average BCS varied with village which ranged from 2.68 to 3.17,but is not different in term of commune and sex of cattle.Besides facing with shortage of feed,the experience with diseases was also another concern,since 85.71%to 95.83%of the households faced this problem last year.Among the clinical signs found,lumpy skin was 100%,i.e.no one escaped from this problem,thus making them aware of vaccinating their cattle against some diseases such as FMD(Foot and Mouth Disease),HS(Hemorrhagic Septicemia)and LSD(Lumpy Skin Disease),but mostly vaccination was used against FMD.Because the LSD has occurred in these areas since 2020,then the seroprevalence was found in high positive up to 72.62%by Enzyme-Linked Immunosorbent Assay(ELISA)test.This positive rate was also varying by villages,ranging from 53.3%to 94.44%.But there was no association between positive cattle with commune,BCS,sex and age of cattle.In conclusion,the cattle production in Romeas Haek district,Svay Rieng province had developed markedly,however the shortage of feed and disease occurrence are the main challenges for farmer cattle producers,especially LSD outbreak last year.However,most of the farmers have been aware of the benefit of vaccination and had vaccinated their cattle against those main disease,such as FMD,HS and LSD.展开更多
Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for ha...Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.展开更多
Potato insurance plays an important role in transferring agricultural risks to promote the potato staple strategy. Understanding farmers’ real preferences for potato insurance attributes is important to improve the p...Potato insurance plays an important role in transferring agricultural risks to promote the potato staple strategy. Understanding farmers’ real preferences for potato insurance attributes is important to improve the potato insurance. In this study, a choice experiment was designed with attributes such as peril, minimum compensation ratio for production loss, types of crops covered by insurance, annual premium per mu after subsidy, and complexity of claims procedures. We constructed a mixed logit model based on a questionnaire survey of 362 potato farmers’ choices of insurance attributes from 24 villages in Dingxi City of Gansu Province using random sampling. The results show that:(1) farmers prefer agricultural insurance with widely perils including output price drop and input cost risk;(2) farmers who have suffered plant disease and insect and pest damage are willing to pay a high premium for the insurance with a high compensation ratio and several types of crops covered;full-time farmers and large-scale farmers preferred insurance products with low complexity of claims procedures. Therefore, new potato insurance design could be considered specifically for different farmer groups such as those who had previous disaster experiences, and large-or small-scale farm operations.展开更多
This study examines the role of farmers’risk attitudes toward fertilizer use in cotton production in China.Contradicting previous studies,this paper theoretically shows that the relationship between farmers’risk ave...This study examines the role of farmers’risk attitudes toward fertilizer use in cotton production in China.Contradicting previous studies,this paper theoretically shows that the relationship between farmers’risk aversion and fertilizer use is not always monotonic.Field survey data were collected to test this relationship using the Cobb–Douglas production function.Results suggest that when the elasticity of fertilizer use and the probability of achieving the desired effects from fertilizer use are high,risk-averse farmers apply more fertilizer than risk-taking farmers.Conversely,when the elasticity of fertilizer use and the probability of achieving the desired effects are low,risk-taking farmers apply more fertilizer than risk-neutral or risk-averse farmers.展开更多
The purpose of this study was to identify if there were differences that existed in the behaviors, attitudes, awareness, and motivating factors that influenced people to shop at farmers’ markets and purchase USDA cer...The purpose of this study was to identify if there were differences that existed in the behaviors, attitudes, awareness, and motivating factors that influenced people to shop at farmers’ markets and purchase USDA certified organic food in two geographic regions: Corvallis, Oregon and Muncie, Indiana. A survey was administered to consumers who shopped at the Minnetrista Farmers’ Market (MFM) and the Corvallis-Albany Farmers’ Market (CAFM) in the summer of 2012 to measure the shoppers’ purchasing perceptions. Specific areas of interest in this study included consumer values towards supporting local farmers and consuming USDA certified organic food. A comparison of responses between regions was analyzed. Results of the study provide insights on consumers’ purchasing attitudes and behaviors regarding USDA certified organic products, and why they chose to shop at Farmers’ Markets. Ideology was the strongest predictor for consumer purchasing behaviors. Understanding how regional differences affect food choice has implications for wellness programs and industry marketing materials.展开更多
Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diplo...Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diploderma species(Diploderma drukdaypo,D.laeviventre,D.batangense,and D.vela),which are endemic to the Qinghai-Tibet Plateau and are currently under state protection.We used the ensembles of small models(ESM)approach and predicted potential distribution ranges of the species in current and two future climate scenarios(SSP126 and SSP585).The degree of overlap between the predicted distribution ranges and existing natural reserves was further analyzed.Habitat preference was examined using a paired quadrat method.Our results predicted that D.drukdaypo has a current distribution range of 600 km^(2),which would decrease to 50 km^(2)and 55 km^(2)under the SSP126 and SSP585 respectively.For D.laeviventre,the current distribution range is 817 km^(2),with minimum changes in the two future climate scenarios(774 km^(2)and 902 km^(2)).For D.batangense,the current distribution range is 875 km^(2),which would expand to 1522 km^(2)and 3340 km^(2)in the two future climate scenarios.Similarly for D.vela,the current distribution range is 1369 km^(2),which would change to 1825 km^(2)and 2043 km^(2)respectively under the two future climate scenarios.The effect of protection of current nature reserves are likely low for those species;we found no overlap(D.drukdaypo,D.laeviventre)or little overlap(D.batangense 2.04%–3.56%,D.vela 15.52%–16.87%)between the currently designated protection area and distribution range under current and future climate scenarios.For habitat preference,stones appear to be the critical habitat element for those species although different species had different stone requirements.Taken together,we provided critical information on potential distribution ranges and habitat preference for four endangered Diploderma species,and confirmed the inadequacy of current nature reserves.The establishment of new or expansion of existing nature reserves is urgent for the conservation of those species.展开更多
This study assesses the literature evidence on climate change risk,resilience,and adaptation measures used among rural farmers in East Africa.A systematic literature review was conducted comprising 30 papers from the ...This study assesses the literature evidence on climate change risk,resilience,and adaptation measures used among rural farmers in East Africa.A systematic literature review was conducted comprising 30 papers from the Web of Science database published during 2000-2022.The results of the literature review showed that climate change risks have direct impacts on agricultural practices,limit rural farmers’resilience,and exacerbate their food insecurity.The most prominent risks are increasingly shorter wet seasons and heat stress,which lead to droughts and food production losses.Responding to climate risks,farmers in East Africa adopt various adaptation strategies such as mixed-and inter-cropping,conservation tillage,early planting,crop diversification,etc.Also,this review summarizes the determinants of climate change adaptation strategy selection by farmers in East Africa,including age,gender,household size,economic status and household assets,landownership and livestock,education and training,etc.Overall,the choice of adaptation strategies to climate change is strongly determined by the gender of household heads,the results of gender as a determinant of adaptation differ greatly between different case studies.Although female-headed households(FHHs)tend to perceive changes in temperature more readily than male-headed households(MHHs),the latter are generally more likely to adopt different adaptation strategies.Despite the resilience and adaptation measures used by rural farmers in East Africa now,improved weather forecasting and early warning systems are needed as a better direction towards the future.展开更多
This paper examined consumers’experiences in and preferences for plant-based meat(PBM)food and their respective correlates,based on data from an online survey of 579 consumers in four major cities in China in early 2...This paper examined consumers’experiences in and preferences for plant-based meat(PBM)food and their respective correlates,based on data from an online survey of 579 consumers in four major cities in China in early 2021.We first described consumers’experiences in consuming and purchasing PBM food and their correlates,and then analyzed consumer preferences using hypothetical choice experiment.The experiment offered consumers various options to purchase burgers made from PBM or animal-based meat(ABM),combined with different countries of origin(COO),taste labels,and prices.Our data showed that respondents hold overall positive attitudes toward PBM food;85 and 82%of respondents reported experience in eating and purchasing PBM food,respectively.More than half of them ate PBM food because they wanted to try new food(58%),or were interested in healthy food(56%).Income,religion,and dietary restrictions were significantly correlated with consumers’experiences in PBM food consumption.Results from the Random Parameter Logit Model based on the hypothetical choice experiment data showed that 79%of respondents chose PBM burgers and were willing to pay an average of 88 CNY for a PBM burger.We also found that 99.8 and 83%of respondents are willing to buy burgers made in China and those with a taste label,with a willingness to pay(WTP)of 208 and 120 CNY,respectively.The heterogeneity test revealed that females and those with at least a bachelor’s degree,higher income,religious beliefs,and dietary restrictions are more likely to buy PBM burgers than their counterparts.展开更多
An important part of Ivorian cocoa production comes from infiltrated classified forests. The objective of this study is to investigate orchard maintenance and post-harvest cocoa treatment practices used by cocoa farme...An important part of Ivorian cocoa production comes from infiltrated classified forests. The objective of this study is to investigate orchard maintenance and post-harvest cocoa treatment practices used by cocoa farmers in infiltrated classified and unclassified areas of Méagui. To do this, 110 producers in two localities of the said zone were individually interviewed from February to April 2022, using a declarative questionnaire. It was found that cocoa orchards in the zone are aging. Nearly 68.55% of producers were heirs and 58.33% of those interviewed were under 46 years of age, with an average age of 43 years. Nearly 84.55% of the producers surveyed mainly use chemical insecticides to control the pests of greatest concern in these localities. Regarding the frequency of insecticide treatments, 11.82% of producers make 1 to 2 applications a year, 29.09% make 3 to 5 applications a year, and 43.64% make at least 6 applications a year. The active substances of the most used products belong to 99% of the Neonicotinoid and Pyrethroid families. Regarding cocoa harvesting and post-harvest operations, 93.64% of the producers carry out a single harvest/month;all do the shelling with mini machetes. Beans are fermented mainly in black plastic tarpaulins or in bags, for a period of 3 to 5 days (65.45%). Drying is done almost entirely (91.82%) on the black plastic tarp. This study shows that cocoa farmers in the areas surveyed do not respect the recommendations issued on phytosanitary practices and post-harvest treatment of cocoa. This non-compliance with the standards of good practices prescribed is particularly more accentuated in the locality located in infiltrated classified zone. It would, therefore, be judicious to revise or redefine the phytosanitary recommendations and carry out sensitization and training-follow-up programs for producers in this important cocoa production area of C?te d’Ivoire.展开更多
基金supported by the National Natural Science Foundation of China(72003082 and 71573130)the Project of Philosophy and Social Science Research in Colleges and Universities in Jiangsu Province of China(2020SJA1015)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)the China Center for Food Security Studies,Nanjing Agricultural University,China。
文摘Farmers’contract breach behavior is cited as one of the major stumbling blocks in the sustainable expansion of contract farming in many developing countries.This paper examines farmers’contract breach decisions from the perspective of time preferences.The empirical analysis is based on a household survey and economic field experiments of poultry households participating in contract farming conducted in Jiangsu Province,China.A discounted utility model and a maximum likelihood technique are applied to estimate farmers’time preferences and the effect of time preferences on contract breach in the production and sales phases are explored with a bivariate probit model.The results show that,on average,the poultry farmers in the sample are generally present biased and impatient regarding future utility.The regression results show that farmers with a higher preference for the present and a higher discount rate are more likely to breach contracts,and time preferences play a greater role in the production phase than in the sales phase.When considering heterogeneity,specific investments and transaction costs promote contract stability only for farmers with a low degree of impatience.Moreover,compared with large-scale farmers,small-scale farmers’contract breach decisions are more significantly affected by their time preferences.These results have implications for contract stability policies and other issues that are impacted by the linking of behavioral preferences to agricultural decisions.
文摘Agricultural investment project selection is a complex multi-criteria decision-making problem,as agricultural projects are easily influenced by various risk factors,and the evaluation information provided by decisionmakers usually involves uncertainty and inconsistency.Existing literature primarily employed direct preference elicitation methods to address such issues,necessitating a great cognitive effort on the part of decision-makers during evaluation,specifically,determining the weights of criteria.In this study,we propose an indirect preference elicitation method,known as a preference disaggregation method,to learn decision-maker preference models fromdecision examples.To enhance evaluation ease,decision-makers merely need to compare pairs of alternatives with which they are familiar,also known as reference alternatives.Probabilistic linguistic preference relations are employed to account for the presence of incomplete and uncertain information in such pairwise comparisons.To address the inconsistency among a group of decision-makers,we develop a pair of 0-1mixed integer programming models that consider both the semantics of linguistic terms and the belief degrees of decision-makers.Finally,we conduct a case study and comparative analysis.Results reveal the effectiveness of the proposed model in solving agricultural investment project selection problems with uncertain and inconsistent decision information.
文摘Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sold to bring in some income. Timely decisions on farm practices such as farm preparation and planting are critical determinants of the seasonal outcomes. In Kenya, most small-scale farmers have no reliable source of information that would help them make timely and accurate decisions. County governments have extension officers who are mandated with giving farmers advisory services to farmers but they are not able to reach most farmers due to facilitation constraints. The mode and format of sharing information is also critical since it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess access to geospatial derived and other crop production information by farmers in four selected counties of Kenya. Specific objectives were to determine the profile of small-scale farmers in terms of age, education and farm size;to determine the type of information that is made available to them by County and Sub-County extension officers including the format and mode of provision;and to determine if the information provided was useful in terms of accuracy, timeliness and adequacy. The results indicated that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary education (34%) or secondary education (29%) and most farmers in all the counties grew maize (71%). Notably, fellow farmers were a source of information (71%) with the frequency of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indicating that they faced challenges while using provided information. The results from the study are insightful and helpful in determining effective ways of providing farmers with useful information to ensure maximum benefits.
基金supported by Natural Science Foundation of China(Grant 61901070,61801065,62271096,61871062,U20A20157 and 62061007)in part by the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant KJQN202000603 and KJQN201900611)+3 种基金in part by the Natural Science Foundation of Chongqing(Grant CSTB2022NSCQMSX0468,cstc2020jcyjzdxmX0024 and cstc2021jcyjmsxmX0892)in part by University Innovation Research Group of Chongqing(Grant CxQT20017)in part by Youth Innovation Group Support Program of ICE Discipline of CQUPT(SCIE-QN-2022-04)in part by the Chongqing Graduate Student Scientific Research Innovation Project(CYB22246)。
文摘The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been considered as a feasible scheme.However,how to efficiently utilize the limited caching resources to cache diverse contents has been confirmed as a tough problem in the past decade.In this paper,considering the time-varying user requests and the heterogeneous content sizes,a user preference aware hierarchical cooperative caching strategy in edge-user caching architecture is proposed.We divide the caching strategy into three phases,that is,the content placement,the content delivery and the content update.In the content placement phase,a cooperative content placement algorithm for local content popularity is designed to cache contents proactively.In the content delivery phase,a cooperative delivery algorithm is proposed to deliver the cached contents.In the content update phase,a content update algorithm is proposed according to the popularity of the contents.Finally,the proposed caching strategy is validated using the MovieLens dataset,and the results reveal that the proposed strategy improves the delay performance by at least 35.3%compared with the other three benchmark strategies.
文摘Introduction: Pesticides are currently an essential component of agricultural production techniques for controlling pests and weeds. In Burkina Faso, non-compliance with good practice in the use of pesticides poses a real health problem for the population. This study examines the health risks associated with pesticide management in rice-growing areas. Material and Methods: A field survey was conducted in Bama, involving farmers, focusing on their socio-demographic characteristics, pesticide usage, and health effects. Cholinesterase levels were measured in subsample of farmers using a portable device. Data were analysed using Microsoft Excel, calculating means and percentages for various practices. Health consultations, protection methods, and pesticide management were studied. Erythrocyte acetylcholinesterase activity was compared before and after treatment. Data were categorised into classes based on inhibition levels, and correlation analyses determined relationships between variables such as age, years of experience, and cholinesterase activity. Results: The results indicate that rice cultivation is mainly carried out by a fairly young population, with nearly 63% being under the age of 50. Common poor practices in pesticide use include improper storage and reuse of leftover pesticides. Seven types of pesticides were identified, including organophosphates such as glyphosate, which was used in 26.7% of cases. This organophosphate has resulted in class B poisoning, causing a 30% - 50% reduction in erythrocyte cholinesterase activity. The health effects of pesticide use are felt by agricultural farmers through various symptoms of poisoning. Conclusion: To reduce the occurrence of pesticide poisoning, it is essential to launch information and awareness campaigns among the population and farmers to promote safe practices in pesticide use in Bama, Burkina Faso.
基金supported by the National Natural Science Foundation of China Project(No.62302540)The Open Foundation of Henan Key Laboratory of Cyberspace Situation Awareness(No.HNTS2022020)+2 种基金Natural Science Foundation of Henan Province Project(No.232300420422)The Natural Science Foundation of Zhongyuan University of Technology(No.K2023QN018)Key Research and Promotion Project of Henan Province in 2021(No.212102310480).
文摘A deep learning access controlmodel based on user preferences is proposed to address the issue of personal privacy leakage in social networks.Firstly,socialusers andsocialdata entities are extractedfromthe social networkandused to construct homogeneous and heterogeneous graphs.Secondly,a graph neural networkmodel is designed based on user daily social behavior and daily social data to simulate the dissemination and changes of user social preferences and user personal preferences in the social network.Then,high-order neighbor nodes,hidden neighbor nodes,displayed neighbor nodes,and social data nodes are used to update user nodes to expand the depth and breadth of user preferences.Finally,a multi-layer attention network is used to classify user nodes in the homogeneous graph into two classes:allow access and deny access.The fine-grained access control problem in social networks is transformed into a node classification problem in a graph neural network.The model is validated using a dataset and compared with other methods without losing generality.The model improved accuracy by 2.18%compared to the baseline method GraphSAGE,and improved F1 score by 1.45%compared to the baseline method,verifying the effectiveness of the model.
文摘Introduction: Females with sickle cell disease (SCD), despite having a delayed pubertal development, are subject to many worries relating to their abilities to conceive, their capacity to maintain a maternofetal-risk-free pregnancy till term and give birth to healthy children without sickle cell disease. Knowing that unplanned pregnancies are more likely to increase maternofetal morbidity and mortality, we sought out to explore the pregnancy preferences in female patients with sickle cell disease to promote healthy conception and childbirth in this vulnerable population. Methodology: We conducted a cross-sectional study involving female patients of child-bearing age with sickle cell disease followed at Laquintinie Hospital Douala or who were members of a local sickle cell association. Pregnancy preferences were determined using the Desire to Avoid Pregnancy (DAP) scale. Factors associated with pregnancy preferences were determined using multivariable linear regression model. Threshold for significance was set at p Results: Seventy-seven patients were included with a mean age of 24.71 ± 5.53 years. Forty patients (51.95%) had one sexual partner and thirteen women (32.5%) used contraceptive methods. Most patients (46.0%) responded “Strongly Agree” or “Agree” to the statement “it would be a good thing for me if I became pregnant in the next 3 months”. The mean DAP score was 1.63 ± 0.91 [1.28 ± 0.82 in those who had a sexual partner and 1.99 ± 0.86 in those who had no sexual partner]. Factors that were positively associated with DAP score were students (b = 0.32, 95% CI [0.21, 0.95], p = 0.003), monthly income ≥ 100,000 FCFA (b = 0.24, 95% CI [0.07, 0.81], p = 0.022), and not having a sexual partner (b = 0.26, 95% CI [0.11, 0.85], p = 0.012). Conclusion: Most female patients with SCD have a low desire to avoid pregnancy. This is especially true for patients who are not students, have a partner and have a low monthly income.
文摘When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of Maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations.
基金the Natural Science Foundation of Inner Mongolia,China(2023JQ01)the National Key R&D Program of China(2019YFA0607103)+2 种基金the Central Government Guides Local Science and Technology Development Fund Projects(2022ZY0224)the Open Project Program of Ministry of Education Key Laboratory of Ecology and Resources Use of the Mongolian Plateau,Hohhot,Inner Mongolia,China(KF2023003)Major Science and Technology Project of Inner Mongolia Autonomous Region:Monitoring,Assessment and Early Warning Technology Research of Biodiversity in Inner Mongolia(2021ZD0011)for financial support.
文摘Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.
文摘This research delves into the hurdles and strategies aimed at augmenting the market involvement of smallholder carrot farmers in Nakuru County, Kenya. Employing a Multinomial Logit (MNL) model, it scrutinizes the factors influencing the selection of marketing outlets among carrot farmers. The findings unveil that a significant majority (81%) of surveyed farmers actively participate in diverse market outlets, encompassing the farm gate, cleaning point, local market, external market, and export market. Notably, pivotal buyers include aggregators, brokers, wholesalers, retailers, and consumers, with transactions predominantly occurring at the farm level. Additionally, the analysis discerns substantial influences of socio-economic characteristics, experiential factors, and geographical proximity on farmers’ choices of market outlets. Specifically, gender, age, land size, farming experience, and distance to markets emerge as critical determinants. Moreover, the study delves into the examination of market margins along the carrot value chain, shedding light on the potential profitability of carrot farming in the region. Remarkably, higher average gross margins are identified in export and external markets, signaling lucrative prospects for farmers targeting these segments. However, disparities in profit distribution between farmers and traders underscore the necessity for interventions to ensure equitable value distribution throughout the value chain. These findings underscore the imperative for tailored interventions to tackle challenges and foster inclusive agricultural development. Strategies such as farmer organizations, contracting, and vertical integration are advocated to enhance market access and profitability for smallholder carrot farmers. Thus, this study enriches our comprehension of the dynamics within carrot value chains and provides valuable insights for policymakers and development practitioners aiming to uplift rural livelihoods and bolster food security.
文摘BACKGROUND Primary thumb carpometacarpal(CMC)osteoarthritis is one of the most common conditions encountered by hand surgeons.Of the vast number of operations that have been proposed,none have demonstrated results significantly superior to trapeziectomy alone.AIM The purpose of our study was to determine why surgeons opt for their technique in treating CMC arthritis.METHODS A cross-sectional survey of active members of the American Society for Surgery of the Hand was conducted to evaluate the reasons behind their preferred technique in the treatment of isolated thumb CMC arthritis.Surgeons were contacted by email once and provided with a link to a de-identified survey consisting of 5 treatment questions and 5 demographic questions.RESULTS Of 950 responses were received.40.5%of surgeons preferred trapeziectomy+ligament reconstruction tendon interposition(LRTI),followed by trapeziectomy+suspensionplasty(28.2%),suture button suspension(5.9%),trapeziectomy alone(4.6%),prosthetic arthroplasty(3.2%),arthrodesis(1.1%),and other(6.6%).Proponents of trapeziectomy+LRTI cited familiarity(73.2%),exposure during fellowship(48.8%)and less proximal migration(60%)to be the main reasons affecting their decision.Surgeons who preferred trapeziectomy+suspensionplasty most reported simplicity(74.9%),fewer complications(45.3%),less proximal migration(43.8%),and avoidance of autogenous tissue harvest(42.7%).Advocates of suture button suspension cited avoidance of autogenous tissue harvest(80.4%),shorter immobilization(76.8%),and quicker recovery(73.2%)with their technique.Advocates of trapeziectomy alone cited simplicity(97.7%),fewer complications(86.4%),and avoidance of autogenous tissue harvest(59.1%).In their comments,45%of surgeons choosing trapeziectomy alone cited evidence as an additional rationale.Advocates of prosthetic arthroplasty cited improved pinch strength(83.3%)and improved range of motion(63.3%),while those preferring arthrodesis cited better pinch strength(90%)and frequently in their comments,durability.Of the surgeons who preferred a technique other than LRTI,41.8%reported they had tried LRTI in the past,citing complexity of the procedure,flexor carpi radialis harvest,and longer operative time as reasons for moving on.CONCLUSION Our study provides an update on current treatment trends and offers new insight into the reasons behind surgeons'decision making in the management of thumb carpometacarpal osteoarthritis.Despite strong Level 1 evidence supporting the use of trapeziectomy alone,our findings demonstrate that most surgeons continue to supplement trapeziectomy with other techniques such as LRTI or suspensionplasty.Several factors including familiarity,personal experience(Level 4 evidence),and comfort may be more influential than Level 1 evidence in determining the techniques in a surgeon's armamentarium.Further prospective studies are needed to determine the optimal technique for surgical management of Eaton stages II-IV CMC arthritis and how these studies will affect surgeons’choice.
文摘The cattle production in Romeas Haek district,Svay Rieng province,was developed remarkably,since there were some households raising cattle in large number,more than 20 heads.The grazing method of cattle was tethering and free grassing in the commune grass,since the natural grass and rice straw were the main source of cattle feed,however some of them supplemented their cattle with crop-byproducts,planting grass or concentrated feed.For the majority,BCS(Body Condition Scoring)of the cattle in those areas was 3 accounting for 52%-73.33%,but it was found the thin cattle has low BCS of 2 accounting for 11.11%to 40.00%and also fat cattle has BCS of 4 up to 27.78%.However,the average BCS varied with village which ranged from 2.68 to 3.17,but is not different in term of commune and sex of cattle.Besides facing with shortage of feed,the experience with diseases was also another concern,since 85.71%to 95.83%of the households faced this problem last year.Among the clinical signs found,lumpy skin was 100%,i.e.no one escaped from this problem,thus making them aware of vaccinating their cattle against some diseases such as FMD(Foot and Mouth Disease),HS(Hemorrhagic Septicemia)and LSD(Lumpy Skin Disease),but mostly vaccination was used against FMD.Because the LSD has occurred in these areas since 2020,then the seroprevalence was found in high positive up to 72.62%by Enzyme-Linked Immunosorbent Assay(ELISA)test.This positive rate was also varying by villages,ranging from 53.3%to 94.44%.But there was no association between positive cattle with commune,BCS,sex and age of cattle.In conclusion,the cattle production in Romeas Haek district,Svay Rieng province had developed markedly,however the shortage of feed and disease occurrence are the main challenges for farmer cattle producers,especially LSD outbreak last year.However,most of the farmers have been aware of the benefit of vaccination and had vaccinated their cattle against those main disease,such as FMD,HS and LSD.
文摘Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest of China(201503001)。
文摘Potato insurance plays an important role in transferring agricultural risks to promote the potato staple strategy. Understanding farmers’ real preferences for potato insurance attributes is important to improve the potato insurance. In this study, a choice experiment was designed with attributes such as peril, minimum compensation ratio for production loss, types of crops covered by insurance, annual premium per mu after subsidy, and complexity of claims procedures. We constructed a mixed logit model based on a questionnaire survey of 362 potato farmers’ choices of insurance attributes from 24 villages in Dingxi City of Gansu Province using random sampling. The results show that:(1) farmers prefer agricultural insurance with widely perils including output price drop and input cost risk;(2) farmers who have suffered plant disease and insect and pest damage are willing to pay a high premium for the insurance with a high compensation ratio and several types of crops covered;full-time farmers and large-scale farmers preferred insurance products with low complexity of claims procedures. Therefore, new potato insurance design could be considered specifically for different farmer groups such as those who had previous disaster experiences, and large-or small-scale farm operations.
基金financial support from the National Natural Sciences Foundation of China(71773150,71273290,and 71934003)。
文摘This study examines the role of farmers’risk attitudes toward fertilizer use in cotton production in China.Contradicting previous studies,this paper theoretically shows that the relationship between farmers’risk aversion and fertilizer use is not always monotonic.Field survey data were collected to test this relationship using the Cobb–Douglas production function.Results suggest that when the elasticity of fertilizer use and the probability of achieving the desired effects from fertilizer use are high,risk-averse farmers apply more fertilizer than risk-taking farmers.Conversely,when the elasticity of fertilizer use and the probability of achieving the desired effects are low,risk-taking farmers apply more fertilizer than risk-neutral or risk-averse farmers.
文摘The purpose of this study was to identify if there were differences that existed in the behaviors, attitudes, awareness, and motivating factors that influenced people to shop at farmers’ markets and purchase USDA certified organic food in two geographic regions: Corvallis, Oregon and Muncie, Indiana. A survey was administered to consumers who shopped at the Minnetrista Farmers’ Market (MFM) and the Corvallis-Albany Farmers’ Market (CAFM) in the summer of 2012 to measure the shoppers’ purchasing perceptions. Specific areas of interest in this study included consumer values towards supporting local farmers and consuming USDA certified organic food. A comparison of responses between regions was analyzed. Results of the study provide insights on consumers’ purchasing attitudes and behaviors regarding USDA certified organic products, and why they chose to shop at Farmers’ Markets. Ideology was the strongest predictor for consumer purchasing behaviors. Understanding how regional differences affect food choice has implications for wellness programs and industry marketing materials.
基金This work was supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2019QZKK0402)Science and Technology Plan Project of Tibet Autonomous Region to Yin QI(Grant No.XZ202201ZY0030G)China Biodiversity Observation Networks(Sino BON-Amphibian and Reptile)。
文摘Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diploderma species(Diploderma drukdaypo,D.laeviventre,D.batangense,and D.vela),which are endemic to the Qinghai-Tibet Plateau and are currently under state protection.We used the ensembles of small models(ESM)approach and predicted potential distribution ranges of the species in current and two future climate scenarios(SSP126 and SSP585).The degree of overlap between the predicted distribution ranges and existing natural reserves was further analyzed.Habitat preference was examined using a paired quadrat method.Our results predicted that D.drukdaypo has a current distribution range of 600 km^(2),which would decrease to 50 km^(2)and 55 km^(2)under the SSP126 and SSP585 respectively.For D.laeviventre,the current distribution range is 817 km^(2),with minimum changes in the two future climate scenarios(774 km^(2)and 902 km^(2)).For D.batangense,the current distribution range is 875 km^(2),which would expand to 1522 km^(2)and 3340 km^(2)in the two future climate scenarios.Similarly for D.vela,the current distribution range is 1369 km^(2),which would change to 1825 km^(2)and 2043 km^(2)respectively under the two future climate scenarios.The effect of protection of current nature reserves are likely low for those species;we found no overlap(D.drukdaypo,D.laeviventre)or little overlap(D.batangense 2.04%–3.56%,D.vela 15.52%–16.87%)between the currently designated protection area and distribution range under current and future climate scenarios.For habitat preference,stones appear to be the critical habitat element for those species although different species had different stone requirements.Taken together,we provided critical information on potential distribution ranges and habitat preference for four endangered Diploderma species,and confirmed the inadequacy of current nature reserves.The establishment of new or expansion of existing nature reserves is urgent for the conservation of those species.
基金the Tertiary Education Trust Fund,National Research Fund 2020 Nigeria(Grant Award-TETF/DR&D-CE/NRF2020/CC/17/VOL.1).
文摘This study assesses the literature evidence on climate change risk,resilience,and adaptation measures used among rural farmers in East Africa.A systematic literature review was conducted comprising 30 papers from the Web of Science database published during 2000-2022.The results of the literature review showed that climate change risks have direct impacts on agricultural practices,limit rural farmers’resilience,and exacerbate their food insecurity.The most prominent risks are increasingly shorter wet seasons and heat stress,which lead to droughts and food production losses.Responding to climate risks,farmers in East Africa adopt various adaptation strategies such as mixed-and inter-cropping,conservation tillage,early planting,crop diversification,etc.Also,this review summarizes the determinants of climate change adaptation strategy selection by farmers in East Africa,including age,gender,household size,economic status and household assets,landownership and livestock,education and training,etc.Overall,the choice of adaptation strategies to climate change is strongly determined by the gender of household heads,the results of gender as a determinant of adaptation differ greatly between different case studies.Although female-headed households(FHHs)tend to perceive changes in temperature more readily than male-headed households(MHHs),the latter are generally more likely to adopt different adaptation strategies.Despite the resilience and adaptation measures used by rural farmers in East Africa now,improved weather forecasting and early warning systems are needed as a better direction towards the future.
基金support from the National Natural Science Foundation of China(71861147003,71925009,72141014).
文摘This paper examined consumers’experiences in and preferences for plant-based meat(PBM)food and their respective correlates,based on data from an online survey of 579 consumers in four major cities in China in early 2021.We first described consumers’experiences in consuming and purchasing PBM food and their correlates,and then analyzed consumer preferences using hypothetical choice experiment.The experiment offered consumers various options to purchase burgers made from PBM or animal-based meat(ABM),combined with different countries of origin(COO),taste labels,and prices.Our data showed that respondents hold overall positive attitudes toward PBM food;85 and 82%of respondents reported experience in eating and purchasing PBM food,respectively.More than half of them ate PBM food because they wanted to try new food(58%),or were interested in healthy food(56%).Income,religion,and dietary restrictions were significantly correlated with consumers’experiences in PBM food consumption.Results from the Random Parameter Logit Model based on the hypothetical choice experiment data showed that 79%of respondents chose PBM burgers and were willing to pay an average of 88 CNY for a PBM burger.We also found that 99.8 and 83%of respondents are willing to buy burgers made in China and those with a taste label,with a willingness to pay(WTP)of 208 and 120 CNY,respectively.The heterogeneity test revealed that females and those with at least a bachelor’s degree,higher income,religious beliefs,and dietary restrictions are more likely to buy PBM burgers than their counterparts.
文摘An important part of Ivorian cocoa production comes from infiltrated classified forests. The objective of this study is to investigate orchard maintenance and post-harvest cocoa treatment practices used by cocoa farmers in infiltrated classified and unclassified areas of Méagui. To do this, 110 producers in two localities of the said zone were individually interviewed from February to April 2022, using a declarative questionnaire. It was found that cocoa orchards in the zone are aging. Nearly 68.55% of producers were heirs and 58.33% of those interviewed were under 46 years of age, with an average age of 43 years. Nearly 84.55% of the producers surveyed mainly use chemical insecticides to control the pests of greatest concern in these localities. Regarding the frequency of insecticide treatments, 11.82% of producers make 1 to 2 applications a year, 29.09% make 3 to 5 applications a year, and 43.64% make at least 6 applications a year. The active substances of the most used products belong to 99% of the Neonicotinoid and Pyrethroid families. Regarding cocoa harvesting and post-harvest operations, 93.64% of the producers carry out a single harvest/month;all do the shelling with mini machetes. Beans are fermented mainly in black plastic tarpaulins or in bags, for a period of 3 to 5 days (65.45%). Drying is done almost entirely (91.82%) on the black plastic tarp. This study shows that cocoa farmers in the areas surveyed do not respect the recommendations issued on phytosanitary practices and post-harvest treatment of cocoa. This non-compliance with the standards of good practices prescribed is particularly more accentuated in the locality located in infiltrated classified zone. It would, therefore, be judicious to revise or redefine the phytosanitary recommendations and carry out sensitization and training-follow-up programs for producers in this important cocoa production area of C?te d’Ivoire.