Typology and Agroecology of Agroecosystems in Vegetation Dynamics in the Ecotones of the Mbam and Inoubou

Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems of Central and South Cameroon, few have come out contribution of the structure of these traditional systems in the dynamics of the vegetation of these forest-savannah ecotones. The present contribution has the overall objective of demonstrating the structural efficiency of agroforests the dynamics of ecotone vegetation, but also in the conservation of biodiversity. To do this, a participatory analysis was carried out with 56 farmers distributed in the five villages of Makénéné. Botanical inventories supplemented socio-economic household surveys. The data collected was subjected to various analyzes (univariate test, analysis of variance, multivariate test, PCA, CAH). The results reveal that 55.2% of agroforests are less than 15 years old and those with an area greater than 1500 m2 predominate (33%). They are mainly young with generally small surface areas. The horizontal structure reveals that the largest diameter classes are those of [20 - 30 cm[ and [10 - 20 cm[ with a very low rate of basal area. Agroforests with trees over 10 m high are dominant in five villages of Makénéné. Two types of structural profiles characterize the agroforestry flora of the area, namely intensive pluristratified home gardens on savannah and intensive pluristratified agroforests under forest-savannah transition vegetation. Principal Component Analysis (PCA) and Ascending Hierarchical Clustering (HAC) show three Agroforest Clusters each. The PCA distribution reveals that woody biomass (Y) is strongly correlated with tree diameter (DBH) and significantly with height (Cluster 2). The age (AAG) (Cluster 1) of these agroforests, on the other hand, remains independent of the density (DST) of these trees (Cluster 3). The agroforests in the Nyokon, Carrière and Mocksud villages are the most effective in terms of conserving woody diversity while the agroforests of the Kinding ndé and Nyokon villages are more efficient in the reforestation processes. These results could be considered as effective and quantifiable tools for the certification of numerous cash crops such as cocoa and coffee, which will make it possible to valorize this local knowledge in terms of scientific and in the development of various programs and writing of technical notes.

Soil Organic Carbon Stock and Soil Quality under Four Major Agroecosystems in the Eastern Flank of Mount Bambouto (West-Cameroon)

Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil quality SQ in the main agroecosystems (AES) of the eastern flank of Mount Bambouto (West, Cameroon). Using multiple statistics tests and principal component analysis (PCA), SOCS and Soil Quality Index (SQI) were computed for each AES. SOCS and SQI were computed based on soil chemical properties and analysis of variance. Topsoil samples (0 - 30 cm) were collected in a different AES and analyzed in the laboratory. The four AES identified and selected are cultivated land (CL), forest areas (FA), mixed areas (MA), and bush areas (BA). Further, multiple comparison tests were used to compare soils from different AES. PCA was used to select the most appropriate indicators that control SOCS and SQ. Several soil properties showed high to very high coefficient of variation within the AES. Organic matter (OM) was significantly high in FA. SOCS and SQ differ significantly (p = 0.000) between the AES. The study further indicates that the main variables controlling SQ within the eastern flank of Mount Bambouto are OM, pHw, N, C/N, and CEC. While the main soil parameters controlling SOCS are OM, OC, BD, C/N, S, and pHKCl.

Climate Change Impacts on Agroecosystems in China:Processes,Mechanisms and Prospects

Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets,requires access to historical research gaps and mapping future research progress for decision making.However,the lack of quantitative and objective analyses to ensure the stability and development of agroecosystems increases the complexity of agro-climatic mechanisms,which leads to uncertainty and undesirable consequences.In this paper,we review the characteristics of climate change in China(1951–2020),reveal the mechanisms of agroecosystem structure in response to climate,and identify challenges and opportunities for future efforts in the context of research progress.The aim is to improve the scientific validity and relevance of future research by clarifying agro-climatic response mechanisms.The results show that surface temperature,precipitation,and frequency of extreme weather events have increased to varying degrees in major agricultural regions of China in 1951–2020.And they have strong geographic variation,which has resulted in droughts in the north and floods in the south.Moreover,climate change has complicated the mechanisms of soil moisture,Net Primary Productivity(NPP),soil carbon pool,and crop pest structure in agroecosystems.This lends to a reduction in soil water holding capacity,NPP,soil carbon content,and the number of natural enemies of diseases and insects,which in turn affects crop yields.However,human interventions can mitigate the deterioration of these factors.We have also realized that the methodology and theory of historical research poses a great challenge to future agroecosystem.Historical and projected climate trends identified current gaps in interdisciplinary integration and multidisciplinary research required to manage diverse spatio-temporal climate change impacts on agroecosystems.Future efforts should highlight integrated management and decision making,multidisciplinary big data coupling,and numerical simulations to ensure sustainable agricultural development,ecological security,and food security in China.

Assessment of soil quality using soil organic carbon and total nitrogen and microbial properties in tropical agroecosystems

Assessment of soil quality is an invaluable tool in determining the sustainability and environmental impact of agricultural ecosystems. The study was conducted to assess the quality of the soils under arable cultivation, locally irri-gated and non-irrigated, forestry plantations of teak (Tectona grandis Lin.) and gmelina (Gme- lina arborea Roxb.), and cashew (Anacardium occidentale Lin.) plantation agro ecosystems using soil organic carbon (SOC), soil total ni-trogen (STN) and soil microbial biomass C (SMBC) and N (SMBN) at Minna in the southern Guinea savanna of Nigeria. Soil samples were collected from soil depths of 0-5 cm and 5-10 cm in all the agro ecosystems and analyzed for physical, chemical and biological properties. All the agro ecosystems had similar loamy soil texture at both depths. The soils have high fer-tility status in terms of available phosphorus and exchangeable calcium, magnesium and po- tassium. The irrigated arable land had significantly (P 6.6 suggesting fungal domination in all the agroecosystems. The forestry plantation soils had higher SMBC and SMBN as a per-centage of SOC and STN respectively than the cultivated arable land soils. Burning for clearing vegetation and poor stocking of forestry planta-tions may impair the quality of the soil. The study suggests that the locally irrigated agro- ecosystem soil seems to be of better quality than the other agroecosystem soils.

Arbuscular Mycorrhizal (AM) Diversity in Prosopis cineraria (L.) Druce Under Arid Agroecosystems

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.

Long-Term Drainage and Nitrate Leaching below Well-Drained Continuous Corn Agroecosystems and a Prairie

Many studies have evaluated nitrate-N leaching from tile-drained agricultural soils, but little longterm research has been performed on well-drained soils commonly throughout the Midwest. Equilibrium tension lysimeters installed at a depth of 1.4 m were used to measure year-round (12 month) nitrate-N leaching below chisel-plow (CP) and no-tillage (NT) continuous corn (Zea mays L.) agroecosystems to determine the potential effects of common agricultural practices on subsurface water quality. The corn systems were fertilized at a rate of 10 kg N ha-1 of starter fertilizer and 180 kg N ha-1 as NH4NO3. For comparison, nitrate-N leaching from a natural ecosystem was performed on a nearby prairie restoration (PR). Drainage, nitrate-N leaching loss, and flow-weighted mean nitrate-N concentrations for 8 years of data (1996-2003) are reported for the CP, NT and PR ecosystems. Results show that 52%, 37%, 16% of cumulative precipitation was collected as drainage, while 18%, 19%, 0.5% of the total N input was leached as nitrate-N in the CP, NT, and PR, respectively. Nearly three-quarters of the total nitrate-N was leached from each ecosystem during the period from 1 April to 30 June. The 8-yr, flow-weighted mean nitrate-N concentration measured in leachate was 9.5, 12.2 and -1 for the CP, NT and PR treatments. Annual drainage volumes and nitrate-N leaching losses were highly variable, stressing the importance of long-term studies capable of measuring year-round drainage for understanding N leaching dynamics and evaluating effects of cropping practices on potential groundwater quality.

Assessment of the Regime of Functioning Agroecosystems Depending on the Climate and Technogenic Pollution of the Soils

Some results of monitoring (for the period from 1992 to 2005) related to transformations of carbon in agroecosystems of Baikal Siberia (Russia) characterized by unpolluted grey forest soils as well as the soils technogenically polluted with heavy metals are discussed with use the unique approach to integrated assessment of the agroecosystem’s functioning regime. The peculiarities of accumulation of carbon in soil microbial biomass and CO2 emission during the years differing in climate conditions are demonstrated. Analysis of formation of net-mineralized and (re)immobilized carbon is conducted, their ratio being used for the purpose of assessment of the level of influence upon the agroecosystem. The agroecosystems having technogenically polluted soils are characterized by processes of the soil microbial biomass reduction and by an obvious increase of CO2 emission into the atmosphere. Negative changes, which are bound up with carbon transformation, are intensified under unfavorable climate conditions. Intensification of processes of carbon net mineralization and, vice versa, lowering the intensity of processes related to carbon (re)immobilization (especially under the effect of soil pollution and climate changes) provoke instability of the agroecosystem and cause formation of a new regime of its functioning.

Effects of Management Practices on Agronomic Parameters in Cocoa Agroecosystems at Peripheral Zone of Ebo Forest Reserve, Littoral Region, Cameroon

The study was carried out to assess the effect of management practices on agronomic parameters of cocoa agroecosystems in the peripheral zone of Ebo Forest Reserve. Purposive random sampling was conducted to establish experimental plots on the farms of willing farmers. Demonstration plots were established and agronomic parameters were monitored for “farmers’ practice (FP) and integrated crop pest and disease management (ICPM) practice” using indicators of Cocoa agro-ecosystem analysis (AESA). The FP and ICPM treatments were replicated in ten sites. From AESA records of agronomic parameters, the “observe, learn, decide and act” (OLDA) model was implemented in the ICPM treatments only. The effects of management practices were analyzed using a two-way analysis of variance (ANOVA), and treatment means compared using Turkey’s T-test at 5% probability. Results of ANOVA between the two Management practices showed that over 50% of the response variables were statistically significant. Means separated through GLM ANOVA with Tukey pairwise comparisons at α = 0.05 showed that 14 (53.8%) out of 26 response variables monitored were statistically significant between the two management practices. Pruning, shade management, phytosanitary harvest, rational use of pesticides, farm sanitation, pod harvesting, breaking, fermentation of beans and drying were regular in the ICPM treatment and time-bound in the FP treatment. The average total production varied from 385.83 kg/ha in FP treatment to 572.8 kg/ha in the ICPM treatment, still below the average standard of 1000 kg/ha. The OLDA model applied in ICPM treatment following AESA is a relevant tool to enhance sustainability in the management of cocoa agroecosystems. Farmers should be sensitized and trained on appropriate farm management techniques and enhance access to extension services as well as make available improved and grafted planting materials to ensure appropriate productivity levels.

Ecosystem Services in Differently Used Agroecosystems along a Climatic Gradient in Slovakia

For analysis and evaluation of potential of agroecosystem (arable land and grassland) services (provisioning, regulating and cultural) in Slovakia we have created a mapping unit combining these input layers: slope topography, soil texture and landuse in four climatic regions. Evaluated potential of agroecosystem services was categorised into five categories (very low, low, medium, high and very high). Our results show that climate has the most significant impact on agroecosystem services. Warm, dry lowland region has a higher potential of provisioning services, regulation of water regime, filtration of pollutants and control of soil erosion in comparison to moderately warm and cold regions. In moderate cold region, more than 90% of the total area of arable land has low potential of water regime regulation and cleaning potential (immobilization of risk elements). In the moderate warm climatic region, there is a high share of categories of low and moderate potential of provisioning services and low and moderate potential of water regime regulation. Majority of the total area of warm climatic region belongs to the categories of moderate to high potential of provisioning services and high potential of regulation of water regime. In this climatic zone low potential categories of risk elements immobilization are present in more than 65% of the arable land total area. On the other hand, in very warm climatic zone, more than 89% of the total area of arable land belongs to the category with a very high cleaning (buffering) potential. Potential of natural conditions for recreation is higher only in moderate cold and moderate warm climatic zones with a higher proportion of area of grassland agroecosystems and protected areas NATURA 2000. Moreover, the methodology developed in this paper is replicable and could be applied by planners in the case that they are proficient in geographical information systems.

Environmental drivers of long-term variations in the abundance of the red hocicudo mouse (Oxymycterus rufus) in Pampas agroecosystems

During the 20th century,there has been an ongoing agricultural expansion and global warming,two of the main determinants influencing biodiversity changes in Argentina.The red hocicudo mouse(Oxymycterus rufus)inhabits subtropical grasslands and riparian habitats and has increased its abundance in recent years in central Argentina agroecosystems.This paper describes the long-term temporal changes in O.rufus abundance in Exaltación de la Cruz department,Buenos Aires province,Argentina,in relation to weatherfluctuations and landscape features,as well as analyzes the spatio-temporal structure of captures of animals.We used generalized liner models,semi-variograms,the Mantel test,and autocorrelation functions for the analysis of rodent data obtained from trappings conducted between 1984 and 2014.O.rufus showed an increase in abundance across the years of study,with its distribution depending on landscape features,such as habitat types and the distance tofloodplains.Capture rates showed a spatio-temporal aggregation,suggesting expansion from previously occupied sites.O.rufus was more abundant at lower minimum temperatures in summer,higher precipitation in spring and summer,and lower precip-itations in winter.Weather conditions affected O.rufus abundance,but there was local variation that differed from global patterns of climate change.

Characteristics of soil quality attributes under different agroecosystems and its implications for agriculture in the Choke Mountain watershed in Ethiopia

Awareness of how soil properties vary over agroecosystems(AES) is essential for understanding soil potentials and improving site-specific agricultural management strategies for a sustainable ecosystem. This study examined the characteristics of soil quality attributes and implications for agriculture in the Choke Mountain watershed in Ethiopia. Forty-seven composite soil samples(0–20 cm deep) were collected from lowland and valley fragmented(AES 1),midland plain with black soil(AES 2), midland plain with brown soil(AES 3),sloppy midland land(AES 4), and hilly and mountainous highlands(AES 5).Ten of 15 soil quality properties were significant(P < 0.05 or 0.01), including silt, exchangeable bases, cation exchange capacity, percent base saturation,p H, organic matter, total nitrogen and available phosphorous(P) across the five AES. However, all properties were variable with coefficients of variation from 7%(total porosity) to 169%(available P) across the AES. Although AES 2and 3 are affected by waterlogging and acidity, these two have better prospects for agriculture, but AES 1, 4, and 5 are unsuitable for agriculture because of soil erosion. Therefore, appropriate and applicable soil management strategies, particularly lime application and organic fertilizer, are fundamental to reversing soil acidity and improving soil fertility.

INTERCROPPING:FEED MORE PEOPLE AND BUILD MORE SUSTAINABLE AGROECOSYSTEMS

Intercropping is a traditional farming system that increases crop diversity to strengthen agroecosystem functions while decreasing chemical inputs and minimizing negative environmental effects of crop production.Intercropping is currently considerable interest because of its importance in sustainable agriculture.Here,we synthesize the factors that make intercropping a sustainable means of food production by integrating biodiversity of natural ecosystems and crop diversity.In addition to well-known yield increases,intercropping can also increase yield stability over the long term and increase systemic resistance to plant diseases,pests and other unfavorable factors(e.g.,nutrient deficiencies).The efficient use of resources can save mineral fertilizer inputs,reduce environmental pollution risks and greenhouse gas emissions caused by agriculture,thus mitigating global climate change.Intercropping potentially increases above-and belowground biodiversity of various taxa at field scale,consequently it enhances ecosystem services.Complementarity and selection effects allow a better understanding the mechanisms behind enhanced ecosystem functioning.The development of mechanization is essential for largescale application of intercropping.Agroecosystem multifunctionality and soil health should be priority topics in future research on intercropping.

Coupling Coordination Analysis of Cropland Intensification and Agroecosystem Services:Evidence from Loess Plateau in Shaanxi Province,China

One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely unexplored.In view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this area.Balance analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling coordination.Results show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to 2020.Agroecosystem service lag was identified as the dominant unbalanced development type.Improving the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess Plateau.The coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious incoordination.Therefore,cropland intensification practices in the area should be optimized to enhance this coordination degree.An upward trend was also observed in the coupling coordination degree from2000 to 2020.The withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern region.Around 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern region.These clustering characteristics are mainly attributed to the environmental suitability of these areas for agriculture and their degree of economic development.

Proximity to corridors benefits bird communities in vegetated interrow vineyards in Mendoza, Argentina

Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in vineyards.Birds provide several contributions to agriculture,for example pest control,recreation and enhancing human mental health,and have intrinsic value.Birds are also ideal model organisms because they are easy to survey,and species respond differently to agricultural land use at different scales.Vegetated borders of crops are key for many species of birds,and distance to the border have been found to be an important factor in vineyard-dominated agroecosystems.We evaluate if there are differences in the bird assemblage,between the interior compared to borders within vineyards,using a hierarchical community occupancy model.We hypoth-esized that occupancy of birds is greater in environments with greater heterogeneity,which in this study was considered to be contributed by the proximity to vegetated corridors.We expected that vineyard borders close to corridors will have higher bird occupancy than the center of the vineyard.The research was conducted in three vineyards with biodiversity-friendly management practices,in Gualtallary,Mendoza,Argentina.Bird surveys were conducted over three breeding seasons from 2018 to 2020.Occupancy and richness of the bird community was more closely associated with the borders adjacent to the corridors than with the interior of the vineyards,as we initially predicted,although the assemblage of birds did not differ much.More than 75%of the registered species consume exclusively or partially invertebrates.Biodiversity-friendly management and ecological schemes,together with vegetated corridors provide multiple benefits for biodiversity conservation.These ap-proaches not only minimize the use of agrochemicals but also prioritize soil cover with spontaneous vegetation,which supports a diverse community of insectivorous bird species,potentially contributing to pest control.

Trade-Offs and Synergie Effects of Regulating Ecosystem Services along an Climatic Gradient in Slovakia

This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We evaluated ecosystem services based on biophysical indicators using an expert scoring system that determines the corresponding soil functions and is part of the existing databases available in Slovakia. This methodological combination enabled us to provide unique mapping and assessment of ecosystem services within Slovakia. Correlation analysis between individual regulating ecosystem services and climate regions, slope, texture, and altitude confirm the statistically significant influence of climate and slope in all agricultural land, arable land, and grassland ecosystems. Statistically significant synergistic effects were established between the regulation of the water regime and the regulation of soil erosion within each climate region, apart from the very warm climate region. Only in a very warm climate region was potential of regulating ecosystem services mutually beneficial for soil erosion control and soil cleaning potential (immobilization of inorganic pollutants).

SUSTAINABLE NITROGEN MANAGEMENT IN AUSTRALIAN AGROECOSYSTEMS: CHALLENGES AND OPPORTUNITIES

Nitrogen is an essential nutrient that supports life,but excess N in the humanenvironment system causes multiple adverse effects from the local to the global scale.Sustainable N management in agroecosystems,therefore,has become more and more critical to address the increasing concern over food security,environmental quality and climate change.Australia is facing a serious challenge for sustainable N management due to its emission-intensive lifestyle(high level of animal-source foods and fossil fuels consumption)and its diversity of agricultural production systems,from extensive rainfed grain systems with mining of soil N to intensive crop and animal production systems with excessive use of N.This paper reviews the major challenges and future opportunities for making Australian agrifood systems more sustainable,less polluting and more profitable.

Changes in nitrogen budget and potential risk to the environment over 20 years(1990–2010) in the agroecosystems of the Haihe Basin, China

The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output,surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop yields.Simultaneously, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010,partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk,decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields.

Transmission of antibiotic resistance genes in agroecosystems: an overview

The use of antibiotics in human medicine andanimal husbandry has resulted in the continuous release ofantibiotics into the environment, which imposes highselection pressure onbacteria to develop antibioticresistance. The spread and aggregation of antibioticresistance genes (ARGs) in multidrug-resistant pathogensisone of the most intractable clinical challenges.Numerous studies have been conducted to profile thepatterns of ARGS in agricultural ecosystems, as this isclosely related to human health and wellbeing. This paperprovides an overview of the transmission of ARGs inagricultural ecosystems resulting from the application ofanimal manures and other organic amendments. The futureneed to control and mitigate the spread of antibioticresistance in agricultural ecosystems is also discussed,particularly from a holistic perspective, and requiresmultiple sector efforts to translate fundamental knowledgeinto effective strategies.

Soil-transmitted helminths and plasmodium falciparum malaria among individuals living in different agroecosystems in two rural communities in the mount Cameroon area:a cross-sectional study

Background:Soil-transmitted helminths(STHs)and Plasmodium falciparum infections remain public health problems in Cameroon.A cross-sectional study was carried out in the Mount Cameroon area to determine the prevalence and intensity of STHs and P.falciparum infections in individuals living in different agroecosystems;to assess the influence of these infections on haematological parameters;and to identify the risk factors associated with STH infections.Methods:STH and malaria parasites were detected using the Kato-Katz method and Giemsa staining of blood films,respectively.Complete blood count values were obtained using an automatic haematology analyser.Soil samples were analysed using the sucrose floatation sedimentation method.Categorical and continuous variables were compared as required and logistic regression models were used to assess the risk factors for STH infections and anaemia.Results:Of the 450 participants examined,STHs,P.falciparum and mixed co-infections were detected in 14.0,33.3 and 5.6%of participants,respectively.Significantly higher prevalences of Ascaris(18.8%)and Trichuris(7.9%)infections were observed in participants from tea plantation areas compared to those from banana and palm plantation areas,with similar trends in egg density.P.falciparum prevalence and parasite density were comparable between the different agroecosystems.The overall prevalence of anaemia was 64.2%.The prevalence of haematological manifestations such as moderate(48.0%)and severe(8.0%)anaemia,leucopenia(26.9%)and microcytosis(30.8%)was significantly higher among Plasmodium-STH co-infected participants.Soil samples from plantations showed the highest prevalences of STH eggs compared to soil samples from areas around pit toilets and public water taps.Living in a tea plantation area(OR=3.07),age(AOR=1.49)and lack of access to potable water(OR=2.25)were identified as risk factors for STH infections,while the age groups 15-25 years(OR=2.928)and 26-35 years(OR=2.832),and being female(OR=2.671)were significant risk factors for anaemia.Conclusions:STHs,malaria and anaemia are still of public health concern in plantation communities.Co-infections negatively influence haematological parameters.The tea farming agroecosystem,age and lack of access to potable water were identified as significant risk factors for STH infections.Trial registration:Not applicable.

Influence of local and landscape environmental factors on alpha and beta diversity of macroinvertebrates in Andean rivers

Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of alpha and gamma diversity by taking into account environmental predictors at local spatial scales(e.g.,micro-and mesohabitats).However,the patterns of beta diversity and the importance of landscape-scale variables have been evaluated to a lesser extent.The objective of this study was to describe the patterns of alpha and beta diversity of benthic macroinvertebrates in the Andean rivers of the Orinoco basin and their relationship with local and landscape environmental variation.A stratified random sampling of macroinvertebrates was carried out at 40 sites(comprising an altitudinal range of between 500 and 2900 m.a.s.l.),local and landscape variables were measured.Our results showed that the variation of alpha diversity was influenced by local and landscape variables,which are directly and indirectly related to the contribution of sediments,substrate composition and flow velocity,providing a heterogeneity of habitats.Global beta diversity was explained by the combined effect of local and landscape variables.Regarding the beta diversity phenomena,turnover was predominant while nestedness presented a minor contribution and both were explained in greater proportion by local descriptors and some landscape variables,specifically those of a geomorphological nature.Our results concur with the view of an environmental and spatial hierarchy within the river habitat and highlight the influence of multiple scales on macroinvertebrate diversity.The above suggests that both local and landscape scales must necessarily be considered for environmental management and the conservation of Andean lotic ecosystems.