Effects Of Land Use Research Articles

Ecological effects of land use and land cover change in the typical ecological functional zones of Egypt

Evaluation the value of ecosystem services can provide crucial reference for formulating ecological protection plans and making informed management decision. This study utilized Landsat remote sensing images as the data source and employed land-use transfer chains and land use transfer matrix methods to compare the ecological effects of land use and land cover change(LUCC) in the two typical ecological functional zones of Egypt, one area isthe northern region of Egypt with the Priority function of Economic Development, another area is the Nasser Reservoir area with the priority function of water conservation. The key findings are as follows: (1)The northern region of Egypt and the Nasser Reservoir exhibited different trends across the ecological functional zones.From 1985 to 2020, the northern region of Egypt is characterized by an increase in arable land and impervious surface,the Nasser Reservoir area is distinguished by the expansion of water and a reduction in sand.(2) Key land transfer patterns vary significantly between the ecological functional zones of the northern region of Egypt and the Nasser Reservoir. From 1985 to 2020, the Egypt’s northern region experienced significant shifts between arable land, sand, and impervious surfaces. The conversion of arable land to impervious surfaces represented 2.41% of the total arable land transfer area, while sand converted to impervious surfaces accounted for 11.68% of the total sand transfer area. In the Nasser Reservoir region, significant conversions occurred between water, grasslands, and sand. Sand converted to water made up 3.83% of the total sand transfer area, while grassland converted to water compriseed 5.38% of the total grassland transfer area. (3) The ecological benefits of the northern region of Egypt and the Nasser Reservoir have increased significantly. In northern region of Egypt, the primary drivers of this increase in ecological service value are the conversion of arable land and grasslands, along with the ecological development and utilization of sand. In the Nasser Reservoir area,the inflow of water and the continued outflow of sands are the main factors contributing to the rise in ecosystem service value. (4) Differentiated LUCC management should be implemented for different ecological functional zones. In northern region of Egypt, the focus should be on balancing ecological security with human development, while the Nasser Reservoir area should prioritize water resource protection and sustainable development. The research findings are not only significant for optimizing LUCC but also for enhancing ecosystem service functions in Egypt.

Spatiotemporal distribution of organochlorine pesticides in the upper La Antigua watershed, Veracruz Mexico

Even though the use of organochlorine pesticides has been prohibited since the last century their presence is still being recorded around the world. In the upper La Antigua watershed, Veracruz, Mexico we have reported concentrations of these contaminants in different compartments of the riverine ecosystems. This is of relevance due to their potential disruptive endocrine effect on the vertebrates drinking the water or feeding in the riverine area. In this study we evaluated concentrations of organochlorine pesticides (OCPs) in streams running throughout mountain cloud forest and two different types of land use, pasture lands and coffee plantations. Water and periphyton samples were collected during the wet and the dry seasons from streams located in independent micro-basins. Spatial explicit analyzes show that the concentrations measured are independent of the distribution of the streams in the geographical area sampled. However seasonal differences were found during the dry season in the water and during the rainy season in periphyton. While OCPs in water support the idea that micro-basins can be used as independent monitoring units, OCPs in periphyton can be indicators of the effect of different land use. Some concentrations of all the OCPs registered had values above the limits for tap water.

Choosing reference land use for carbon and biodiversity footprints

Abstract Purpose Carbon and biodiversity footprints are increasingly calculated. However, little attention has been paid to the coherency of methodological choices and interpretation of the footprint results. This paper aims to clarify the coherency between the choice of reference land use and carbon and biodiversity footprints and discuss the challenges encountered. Methods First, we analyse features of reference land use options proposed in ISO 14067 (2018) i.e. business as usual, projected future, target, potential natural regeneration and historic baseline. Second, we discuss the connection between temporal scope and life cycle of land use. Third, we provide guidance on how to choose reference land use coherently. Fourth, we discuss specific issues related to carbon and biodiversity footprints and their relationship to reference land use. Finally, we provide conclusions and recommendations for further conceptual development. Results and discussion Choice of reference land use and determination of temporal scope of a study may significantly influence the assessment of carbon or biodiversity footprints. If the aim of a footprint study is to assess the effects of land use, reference land use should describe dynamically non-use of land. Thus, potential natural regeneration or continuation of natural state (if it is the starting point) of land is the coherent reference land use in this case. If the aim of a footprint study is to assess the effects of a decision to change land use or its management, reference land use should describe dynamically alternative use of land expected without the studied decision. Business as usual or projected future is a coherent reference land use in this case. Historic baseline or target reference land use may be useful in comparing the ecosystem value of the studied land use with a pre-set historic baseline or (policy) target. Conclusions We conclude that coherent choice of reference land use for carbon or biodiversity footprints depends on the goal and scope of a study. Beyond methodological coherency, issues related to the reliability and availability of appropriate data are relevant and vary between reference land use choices. However, difficulties in the assessment should not justify incoherent choices. We recommend that uncertainties are not overlooked but incorporated in the assessment and considered in the interpretation of the results. In addition, we recommend that key methodological choices, including the definition of the purpose of a study, chosen temporal scope and applied reference land use, should be clearly and transparently presented.

Combined effects of flood, drought and land use dominate water quality and nutrient exports in Jialing River basin, SW China

Climate change and the associated increase in hydroclimatic extremes necessitate a deeper understanding of the resulting water quality responses. This study investigates the combined impacts of hydroclimatic extremes and land uses on water quality of the Chinese Jialing River, of which the middle and downstream areas experienced a flood in 2021 and a severe drought in 2022. Water Quality Index (WQI) and nutrient loads were assessed using daily data from 22 monitoring stations across the Jialing River and its two tributaries, the Qujiang River and Fujiang River, over 2021–2022. The results indicate a slight upward trend in water quality, as reflected by the WQI, for the tributaries from 2021 to 2022, while a declining trend was observed in the mainstream. Floods had a more pronounced impact on water quality than droughts, particularly on nutrient concentrations, and both dilution and flushing effects were observed as discharge increased in the Jialing River and its tributaries. Notably, water quality deterioration was most pronounced in the downstream areas with land uses dominated by cropland and built-up area, where intensified rainfall distributed and exacerbated nutrient losses in the rainy seasons. Nutrient fluxes, including Chemical Oxygen Demand (COD), Total Phosphorus (TP), and Total Nitrogen (TN), were closely linked to discharge, with hydroclimatic extremes therefore significantly affecting nutrient exports. This study elucidates the complex interactions between land use, extreme weather and water quality in the Jialing River Basin. Our findings underscore the need to strengthen the management of non-point source pollutants in the downstream areas of the Jialing River to address the challenges posed by anticipated increases in extreme rainfall in the near future.

Functional diversity of ground beetles improved aphid control but did not increase crop yields on European farms.

Land-use intensification is often associated with a decline in functional diversity, potentially undermining the provision of ecosystem services. However, how changes in traits affect ecosystem processes remains poorly understood. Variation in trait values among species in a community may drive ecosystem processes. Alternatively, the mass ratio hypothesis proposes that trait values of the dominant species in a local community are related to ecosystem processes. Using data from 159 farms in six European countries, we quantified the impact of local and landscape-level land-use intensity on ground beetles as pest control agents. We then assessed the extent to which functional diversity and community-weighted mean trait values relate to pest control and cereal yield. In addition, we assessed how the responses to land use and the effects of different species on pest control and yield varied with their traits to compare the relative impact of the traits studied. Functional diversity of ground beetles improved aphid removal, but did not translate into higher crop yields. Pest control of aphids was enhanced by a higher proportion of smaller, mobile ground beetles with a preference for the vegetation layer. Smaller, predatory ground beetles in communities improved crop yield. The magnitude of responses to land-use intensification and the effects on pest control and yield were more strongly influenced by body size than other traits. Our study provides evidence that reduced management intensity can improve pest control by supporting small-sized, macropterous ground beetles. In contrast to the claims of ecological intensification, our joint analysis of the direct effects of land use on yield and indirect effects via functional diversity of ground beetles and pest control suggests that ecosystem services by ground beetles cannot compensate for the yield gap due to a reduction in land-use intensity.

The effects of land use on soil carbon stocks in the UK

Abstract. Greenhouse gas stabilisation in the atmosphere is one of the most pressing challenges of this century. Sequestering carbon in the soil by changing land use and management is increasingly proposed as part of climate mitigation strategies, but our understanding of this is limited in quantitative terms. Here we collate a substantial national and regional data set (15 790 soil cores) and analyse it in an advanced statistical modelling framework. This produced new estimates of the effects of land use on soil carbon stock (Sc) in the UK, different in magnitude and ranking order from the previous best estimates. Soil carbon stocks were highest in woodlands, followed by rough grazing, semi-natural grasslands, and improved grasslands, and they were lowest in croplands. Estimates were smaller than the previous estimates, partly because of new data, but mainly because the effect is more reliably characterised using a logarithmic transformation of the data. With the very large data set analysed here, the uncertainty in the differences among land uses was small enough to identify consistent mean effects. However, the variability in these effects was large, and this variability was similar across all surveys. This has important implications for agri-environment schemes seeking to sequester carbon in the soil by altering land use, because the effect of a given intervention is very hard to verify. We examined the validity of the “space-for-time” substitution, and, although the results were not unequivocal, we estimated that the effects are likely to be overestimated by 5 %–33 %, depending upon land use.

Flowering plant communities mediate the effects of habitat composition and configuration on wild pollinator communities

Abstract There is strong evidence that landscape‐scale factors such as habitat diversity, composition and configuration are important drivers of declines in pollinators and pollination services. However, context and species‐specific responses make it challenging to draw general conclusions about the most important components of landscapes that support diverse and abundant pollinator communities. In this study, we took a functional‐traits approach to community assembly and tested the hypothesis that landscape properties act most strongly on pollinators indirectly, through their influence on flowering plant communities. Using plant and pollinator data from 96 landscapes in Britain, we tested the associations between plant and pollinator communities and local environmental factors, such as habitat cover and configuration, using path analysis based on Mantel and partial Mantel statistics. When all pollinators were considered, we found that the environmental factors had stronger links to the composition of flowering plant communities than to the composition of pollinator communities. Further, the flowering plant community was strongly linked to the pollinator community suggesting a mediating role between land use and pollinators. When separating the pollinator community into taxonomic groups, we found the same result for hoverflies, but wild bees were linked to both environmental factors and flowering plants. We further explored these links with structural equation models using the response‐effect trait framework as a guiding principle. We found strong evidence that land‐use composition and configuration influence the trait distribution and functional diversity of the pollinator community via plant community composition. These findings suggest that the indirect effect of land use on pollinators via flowering plants should be considered in informing the design of pollinator friendly landscapes and in future research of the effects of land use and management on wild pollinators. Read the free Plain Language Summary for this article on the Journal blog.

Analysing Thermal Land Surface Characteristics and Urban Expansion in Kenitra City, Morocco, using Remote Sensing and GIS

Abstract This research investigates how land use and cover the affect land surface temperature in Kenitra. It employs Geographic Information System techniques and remote sensing methods to monitor and control surface temperature changes. The present study integrates remote sensing and geographic information system to process satellite images. Furthermore, it focuses, also, on analyzing land surface temperature and its correlation with land cover changes over three time periods (1989, 2000, 2020) using landsat satellite data. Thus, supervised classification is employed to map these changes and derive urban heat islands from thermal band data. This study provides a comprehensive evaluation of the relationship between land use and land surface temperature. It utilizese a landscape dynamics assessment based on multi-source and multi-sensor remote sensing technologies. Specifically, the study uses landsat satellite data (TM for 1989 and OLI-8 for 2002 and 2020) to assess the effects of land use and land cover changes on land surface temperature distribution in the Kenitra city. Spatial and statistical analyses are performed by comparing maps from remotely sensed data generated using geographic information system. Therefore, these analyses reveal various changes in the kenitra region between 1989 and 2020. The primary changes observed include an increase in built-up areas and bare ground with a decrease alongside in natural areas (vegetation, etc.). The average temperatures in 1989, 2002, and 2020 were 29°C, 31.05°C, and 32°C, respectively. The obtained results are valuable for planning and managing climate scientists, land-use planners, and researchers focusing on sustainable urbanization areas. The study’s findings will assist urban planners and policymakers in adopting appropriate measures for sustainable planning in the city to mitigate the adverse effects of land surface temperature.

Exploring action-law of microplastic abundance variation in river waters at coastal regions of China based on machine learning prediction

Surface waters, particularly the river systems, constitute a vital freshwater resource for human beings and aquatic life on Earth. In economically developed and densely populated coastal regions, river water is facing severe microplastic pollution, posing a threat to public health and ecological safety. Reliable prediction of microplastic abundance (MPA) can significantly reduce the costs associated with microplastic field sampling and analysis. This study employed spatial correlation, geographical detector, principal component analysis and five mainstream machine learning models to analyze 79 datasets of MPAs in seven coastal areas of China and performed correlation, regression and attribution analyses based on 19 terrestrial influencing factors that potentially affect the MPA life cycle processes (generation, aging, and migration). The results showed that the Neural Network (NN) and the Gaussian Process Regression (GPR) models achieved the best prediction performance, with the predicted R2 close to 1. Principal component analysis and Shapley additive explanations concluded that meteorological factors, in particular the annual geotemperature, surface solar radiation, and annual relative humidity, had a key influence on the aging of microplastics. The second key factor in improving the MPA prediction ability was the dynamic description of microplastic migration, which was primarily governed by hydrological factors such as annual precipitation and average terrain slope. Unexpectedly, the effects of land use and level of urbanization were relatively small in describing the generation of microplastics. Only the percentage of built areas was strongly correlated with the MPA levels. Note that the MPA prediction and its contribution factors may vary across different basins. Nevertheless, the findings of this study are applicable to predicting and analyzing the distribution of microplastics in other coastal rivers, and for indicating the main contributing factors, ultimately serving as a basis for guiding microplastic pollution control strategies in different river basins.

THE CURRENT STATE OF AGRICULTURAL LAND USE IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT

This article discusses the rational use of agricultural land, taking into account structural and resource indicators for sustainable development. The effectiveness of land use in farms with different forms of land ownership depends on increasing labor productivity, strengthening the economy regime, increasing the intensification of production, using internal reserves and opportunities for agricultural production and, especially, rational use of land. The basis for the formation of sustainable land use should be strict observance of the established relationships between disturbed and undisturbed territories. Undisturbed territories should be considered as a stabilizing factor neutralizing anthropogenic impacts on the landscape. In this regard, the tasks of preserving productive agricultural land, optimizing arable land and acreage in terms of quantitative and qualitative characteristics of land are becoming a priority. The solution of these tasks is connected with the improvement of technologies for maintaining and increasing the bioproductivity of agricultural lands, the development of technologies for rational land management, land use and land protection, the creation of effective organizational and legal mechanisms for managing agricultural lands, as well as the development of state monitoring of agricultural lands. In order to approach the practice of determining the efficiency of land use, it is necessary to focus in more detail on its factors according to the selected functional subsystems and types of efficiency.

Effects of Agricultural Land Use on Desert Soil Classification in Holy Karbala Governorate

This study was conducted to evaluate physical, chemical, and morphological features to classify soils at the subgroup level. The research area, located west of Karbala, consists of three locations, each comprising pedons in both cultivated and uncultivated lands. GPS coordinates were recorded, and morphological descriptions of pedon horizons were made in accordance with the American Soil Survey Manual. This study investigates the effect of agricultural land use on the classification of desert soils in the Holy Karbala Governorate. The results revealed that the dry climate caused diversity in the morphological features of the soils, mainly in horizon type, thickness, and arrangement. Agricultural usage had an impact on diagnostic horizons, particularly the gypsic horizon, and features such as soil color, structure, organic matter, carbonate minerals, gypsum, and root distribution. However, there was no substantial impact on soil texture development, and soils did not show a consistent pattern of soil separation distribution with depth, indicating weak pedogenic processes. The most common texture classes were loamy sand, sandy loam, and sand, with sand contents ranged from 902.08 to 574.12 g kg. Soil bulk density differed from 1.67 to 1.30 Mg m³, with lower values in farmed areas. Chemical properties were influenced, with soil pH ranging from 8.36 to 7.54, electrical conductivity (EC) from 5.46 to 2.03 dS m, cation exchange capacity (CEC) from 15.25 to 2.05 meq.100g, organic matter from 43.51 to 1.18 g kg, carbonate minerals from 461.18 to 174.06 g kg, and calcium sulfate from 182 to 21 g kg. The soils were classed as Aridisols because they were found in a dry desert with an Aridic moisture regime. The presence of distinctive saline layers such as Calcic and Gypsic was discovered, resulting in the classification of cultivated soils as Typic Haplocalcids and uncultivated lands as Typic Calcigypsids.

Dynamic Monitoring and Analysis of Ecological Environment Quality in Arid and Semi-Arid Areas Based on a Modified Remote Sensing Ecological Index (MRSEI): A Case Study of the Qilian Mountain National Nature Reserve

The ecosystems within the Qilian Mountain National Nature Reserve (QMNNR) and its surrounding areas have been significantly affected by changes in climate and land use, which have, in turn, constrained the region’s socio-economic development. This study investigates the regional characteristics and application requirements of the ecological environment in the arid and semi-arid zones of the reserve. In view of the saturated characteristics of NDVI in the reserve and the high-altitude saline-alkali environmental conditions, this study proposed a Modified Remote Sensing Ecology Index (MRSEI) by introducing the kernel NDVI and comprehensive salinity index (CSI). This approach enhances the applicability of the remote sensing ecological index. The temporal and spatial dynamics of ecological and environmental quality within the QMNNR from 2000 to 2022 were quantitatively assessed using the MRSEI. The effect of land use on ecological quality was quantified by analyzing the MRSEI contribution rate. The findings in this paper indicate that (1) in arid and semi-arid regions, the MRSEI provides a more precise representation of surface ecological environmental quality compared to the remote sensing ecological index (RSEI). The high correlation (R2 = 0.908) and significant difference between MRSEI and RSEI demonstrate that MRSEI enhances the accuracy of evaluating ecological environmental quality. The impact of land use on ecological quality was quantitatively assessed by analyzing the contribution rate of the MRSEI. (2) The ecological quality of the QMNNR exhibited an upward trend from 2000 to 2022, with an increase rate of 1.3 × 10−3 y−1. The area characterized by improved ecological and environmental quality constitutes approximately 53.68% of the total area. Conversely, the ecological quality of the degraded areas accounts for roughly 28.77%. (3) Among the various land use types, the improvement in ecological environmental quality within the reserve is primarily attributed to the expansion of forest and grassland areas, along with a reduction in unused land. Forest and grassland types account for over 90% of the total area classified with “good” and “excellent” ecological grades, whereas unused land types represent more than 44% of the total area classified with “poor” ecological grades. Overall, this study provides a valuable framework for analyzing ecological and environmental changes in arid and semi-arid regions.

Arbuscular mycorrhizal fungal diversity in agricultural fields is explained by the historical proximity to natural habitats

Soil microbes are essential to maintain terrestrial ecosystem functionality. However, their diversity is threatened by land-use change, such as agricultural expansion and intensification. One important microbial group mediating the exchange of nutrients between plants and soil is arbuscular mycorrhizal (AM) fungi. The response of microorganism diversity to present and past habitat amount has been poorly studied. Here, we evaluate the potential role of current and historical natural habitat availability in explaining the diversity of AM fungi in arable fields. We conducted a spatially intensive sampling of three agricultural fields in Estonia. Soil AM fungal diversity was determined by soil DNA metabarcoding. We related AM fungal species richness, along with beta diversity components (turnover and nestedness), to abiotic conditions and natural habitat area availability at different spatial scales and time periods. Our findings showed a positive relationship between AM fungal richness and the amount of natural habitat area. Specifically, current AM fungal species richness was best explained by the amount of natural habitat from 130 years earlier, indicating a legacy effect of past land use on current soil biodiversity. The amount of past natural areas was negatively related to the beta diversity turnover component, indicating a replacement of AM fungal species in disturbed sites. While biodiversity-friendly farming is useful in promoting diverse soil biota, historical legacies can be persistent. Maintaining natural habitats around agricultural fields can further promote soil AM fungal diversity for future generations.

Climate change driven by LUCC reduced NPP in the Yellow River Basin, China

Anthropogenic activities and the resulting climate change affect the type, structure, and function of ecosystems. Understanding vegetation dynamics related to anthropogenic activities and climate change is critical to address the terrestrial carbon cycle in the context of global warming. The objective of this study is to quantify the effects of human-induced land use and land cover change (LUCC) and LUCC-induced climate change on terrestrial net primary productivity (NPP) in the Yellow River Basin (YRB) during 2000–2020 using Weather Research and Forecasting (WRF) model and Integrated Biosphere Simulator (IBIS) model through different experimental scenarios. Results indicated that LUCC can cause an increase in NPP of 1.2 ± 0.67 gC m−2 yr−1 in YRB. The increased precipitation and decreased temperature due to LUCC showed weak negative effect on annual mean NPP in YRB (−0.2 ± 0.74 gC m−2 yr−1). The coupling of LUCC and LUCC-induced climate change increased annual mean NPP approximately 0.6 ± 0.86 gC m−2 yr−1. The impacts of LUCC and LUCC-induced climate change and their coupling effects on NPP were greatest in spring, increasing NPP by 5.1 ± 0.51, 3.4 ± 0.41, and 6.1 ± 0.79 gC m−2 yr−1, respectively. These findings provide important guidance for the sustainable and adaptive management of terrestrial ecosystems in river basin in the context of global change.

Land use to agriculture and planted forests strongly affect the genetic diversity of Baccharis crispa Spreng., a native herb of South America

Abstract Human population growth constantly requires an increase in the production of food and products from the timber industry. To meet this demand, agriculture and planted forests are advancing over natural areas. In view of this, it is necessary to know the effects of land use for different purposes (grain production, pastures, planted forests, fruit production, among other uses) on the genetic diversity of populations of native species. This knowledge can assist in land use planning as well as in the development of conservation strategies for native species. In this study, we evaluated the effect of land use for agriculture (mainly for cereal production) and planted forests on the genetic diversity of Baccharis crispa Spreng., a herb native to South America. To achieve our goals, we compared population genetic data obtained with three molecular markers (microsatellites, ISSR [inter-simple sequence repeat] and isoenzymes) with data on land use for agriculture and planted forests from 15 different locations. Our results showed that regardless of the molecular marker used, the greater the use of land for agriculture and planted forests, the lower was the genetic diversity of B. crispa populations. Baccharis crispa is a semi-perennial species that needs at least one year to reach its reproductive period, which is prevented in agricultural areas due to the land being turned over or dissected with herbicides every six months. In the studied regions, the planted forests are of eucalypt and/or pine, which besides being species with a high production of allelopathic substances, produce strong shading and B. crispa is a species that inhabits open grassland that needs high incidence of sunlight for development. The data obtained in our study can assist in the decision-making to use land in order to reconcile the production of supplies for humanity and for the conservation of nature.

Differences in soil biological activity and soil organic matter status only in the topsoil of Ferralsols under five land uses (Allada, Benin)

Land use change on the Ferralsols of the Allada Plateau in southern Benin has led to a slight decline in soil organic carbon (SOC) stocks over the last two decades. However, as in many African landscapes, detailed characterisation and quantified data on the SOC stocks and soil biological activity under major land uses are still poorly understood. The aim of this study was to characterise the biological activity and organic matter status of Ferralsols (0–30 cm) under the five major land uses on the Allada Plateau, i.e., forests, tree plantations, young and adult palm groves, and croplands (pineapple, maize). Soil biological activity was assessed using the standardised litter decomposition method (Tea bag index) and soil respiration (during a 28-day soil incubation). Soil organic matter status was characterised by quantifying SOC pools: soil microbial biomass carbon (MB-C), potassium permanganate oxidisable carbon (POX-C), and SOC associated to soil particle-size fractions (e.g. particulate organic matter, POM, and SOC associated to the clay soil fraction). The results indicated that SOC pools and biological activity were lower in tree plantations than in forests. The standardised litter decomposition was also slower in tree plantations than in forest. In croplands and palm groves, SOC pools and soil microbial biomass and respiration were lower than in forests and tree plantations. This high level of biological activity in forests, and at a lesser level in tree plantations, was effective in accumulating carbon in C pools associated to the clay fraction. Agricultural land uses, such as croplands and palm groves decreased all the soil C pools even those associated to the clay fraction, except for POX-C. However, these land-use effects on SOC pools decreased strongly with depth. At 10–30 cm, the differences in SOC pools or soil respiration between the five land uses were no more noticeable. Our results indicated that the amount of organic inputs was an essential factor to sustain high soil biological activity and SOC stabilisation in the clay size fraction, but only in the topsoil. Maintaining forests in the landscape is a priority in order to preserve SOC stocks and soil biological activity, which neither monospecific tree plantations nor cultivation can do at the same level.

Bayesian spatio-temporal modeling to assess the effect of land-use changes on the incidence of Cutaneous Leishmaniasis in the Brazilian Amazon

Cutaneous Leishmaniasis (CL) is a vector-borne disease caused by a protozoan of the genus Leishmania and is considered one of the most important neglected tropical diseases. The Brazilian Amazon Forest harbors one of the highest diversity of Leishmania parasites and vectors and is one of the main focuses of the disease in the Americas. Previous studies showed that some types of anthropogenic disturbances have affected the abundance and distribution of CL vectors and hosts; however, few studies have thoroughly investigated the influence of different classes of land cover and land-use changes on the disease transmission risk. Here, we quantify the effect of land use and land-cover changes on the incidence of CL in all municipalities within the Brazilian Amazon Forest, from 2001 to 2017. We used a structured spatiotemporal Bayesian model to assess the effect of forest cover, agriculture, livestock, extractivism, and- deforestation on CL incidence, accounting for confounding variables such as population, climate, socioeconomic, and spatiotemporal random effects. We found that the increased risk of CL was associated with deforestation, especially modulated by a positive interaction between forest cover and livestock. Landscapes with ongoing deforestation for extensive cattle ranching are typically found in municipalities within the Amazon Frontier, where a high relative risk for CL was also identified. These findings provide valuable insights into developing effective public health policies and land-use planning to ensure healthier landscapes for people.

Pattern and change of NDVI and their environmental influencing factors for 1986–2019 in the Qinling-Daba Mountains of central China

Previous studies have shown that climate change and human activities play an important role in the vegetation dynamics in the Qinling-Daba Mountains of central China. However, which environmental factors including climate, topography, soil and human activities play an important role in the vegetation dynamics and its spatial pattern in the Qinling-Daba Mountains remains to be further clarified. Based on the normalized difference vegetation index (NDVI) data of the growing season from 1986 to 2019 synthesized by Landsat series satellite data on Google Earth Engine, this study aimed to further investigate the spatial pattern of NDVI and its dynamics, and clarify its environmental controlling factors in the Qinling-Daba Mountains using the methods of spatial analysis and Geodetector. The results showed that: (1) the spatial pattern of NDVI in the study area had a U-shaped NDVI distribution in latitude, anti-U-shaped patterns in longitude and with increasing altitude. (2) 2005 was the year of NDVI breakthrough increase, and the vegetation dynamics was divided into two periods according to the result of MK mutation test: the slow increasing period with an increasing rate of 0.25%/a from 1986 to 2004 (R2 0.74), and the rapid increasing period with an increasing rate of 0.30%/a from 2005 to 2019 (R2 0.92). (3) Topography regulating local hydrothermal conditions and soil enriching nutritions played more important influence on NDVI spatial pattern than climate factors (temperature and precipitation) at the regional scale. The effect of land use on NDVI change was stronger than that of climate warming (temperature), and the climate warming in recent decades played a more important role than precipitation on the NDVI dynamics. Research on vegetation patterns, changes and their environmental influencing factors will help the government and other related agencies to formulate plans or policies for infrastructure development and land management, ecological restoration.

The Effects of Land Use and Landform Transformation on the Vertical Distribution of Soil Nitrogen in Small Catchments

The diversity of land use and consolidation is fundamental to ensuring sustainable development. However, the impact of diverse land uses and consolidation on the well-known shallow accumulation pattern of soil nitrogen (N) remains unclear. This existence of this knowledge gap severely constrains the sustainable production of newly created farmland. Therefore, the objective of this study was to investigate the effects of land use and gully land transformation on the vertical distribution of soil N in agricultural and nature catchments. Methodologically, soil nitrate (NO3−), ammonium (NH4+) and total nitrogen (TN) were measured to a depth of 100 cm in the hillslope forestland, grassland and gully cropland areas of the treated (gully landform reshaping) and untreated (natural gully) catchments on the Chinese Loess Plateau (CLP). The results indicated that soil N in the hillslope forestland and grassland exhibited a shallow accumulation pattern, while the vertical distribution of soil N in the gully cropland areas displayed a homogeneous, random or deep accumulation pattern. In the hillslope areas, vegetable cover was the dominant factor controlling N variation in the topsoil. In contrast, in the gully areas, the interaction of landform transformation and hydrology was the primary factor influencing the distribution of soil N. In the treated catchment, soil NO3− exhibited a significant deep accumulation pattern in the newly created farmland through gully landform reshaping. In the untreated catchment, soil NH4+ showed a significant deep accumulation pattern in the undisturbed natural gully. This study provides valuable insights into how land use and gully landform transformation affect the soil N profile. This information is crucial for the sustainable development and scientific management of valley agriculture at the catchment scale.

Hydrology and water quality drive multiple biological indicators in a dam-modified large river

Freshwater biodiversity is increasingly threatened by dams and many other anthropogenic stressors, yet our understanding of the complex responses of different biotas and their multiple facets remains limited. Here, we present a multi-faceted and integrated-indices approach to assess the differential responses of freshwater biodiversity to multiple stressors in the Yangtze River, the third longest and most dam-densely river in the world. By combining individual biodiversity indices of phytoplankton, zooplankton, periphyton, macroinvertebrates, and fish with a novel integrated aquatic biodiversity index (IABI), we disentangled the effects of hydrology, water quality, land use, and natural factors on both α and β diversity facets in taxonomic, functional, and phylogenetic dimensions. Our results revealed that phytoplankton and fish species and functional richness increased longitudinally, while fish taxonomic and phylogenetic β diversity increased but phytoplankton and macroinvertebrate β diversity remained unchanged. Hydrology and water quality emerged as the key drivers of all individual biodiversity indices, followed by land use and natural factors, with fish and phytoplankton showed the strongest responses. Importantly, we found that natural, land use, and hydrological factors indirectly affected biodiversity by altering water quality, which in turn directly influenced taxonomic and phylogenetic IABIs. Our findings highlight the complex interplay of multiple stressors in shaping freshwater biodiversity and underscore the importance of considering both individual and integrated indices for effective conservation and management. We propose that our multi-faceted and integrated-indices approach can be applied to other large, dam-modified river basins globally.