Intensity Of Human Disturbance Research Articles

Assessment of dynamic hydrological drought risk from a non‐stationary perspective

AbstractThe stationarity hypothesis of hydrometeorological elements has been questioned in the context of global warming and intense human disturbance. The conventional drought index and methods of frequency analysis may no longer be applicable for hydrological drought risk evaluation under a changing environment. In this study, a new dynamic hydrological drought risk evaluation framework is proposed for application to the Hanjiang River basin (HRB), which simultaneously considers the non‐stationarity in the construction of drought index as well as in the frequency analysis. First, a non‐stationary standardized runoff index (NSRI) is developed using a generalized additive model for location, scale and shape (GAMLSS) framework. Then, hydrological drought characteristics including duration and severity are identified, and their marginal distributions are established. Finally, based on the dynamic copula, considering the non‐stationarity of the dependence structure, the dynamic joint probability distribution, conditional probability distribution and return period of the bivariate hydrological drought properties are analysed. Results showed that NSRI, which integrates the impacts of climate change and anthropogenic activities on the non‐stationarity of runoff series, had a better ability to capture runoff extremes than had SRI. In addition, it is indispensable to consider the non‐stationarity of the dependence structure between variables when discussing the multivariate joint risk of hydrological drought. The risk of hydrological drought in the study area has shown an increasing trend in the past 65 years, and the drought conditions from upstream to downstream have been alleviated first and then intensified. This study provides valuable information for regional drought risk estimation and water resources management from a non‐stationary perspective.

Human activities are intensifying the spatial variation of landslides in the Yellow River Basin

Human activities are a triggering factor for landslides in the Yellow River Basin (YRB, China). However, the extent to which the spatial distribution of landslides is affected by human activities is unclear. We constructed a human activity intensity index (HAII) based on nighttime light data and land cover data. Regression and dominance analyses were used to compare the effects of the HAII, precipitation, distance to river, distance to fault, topographic relief and slope on the landslides spatial density (LSD). The results showed that in the YRB, the HAII, as a dominance influencing factor, had a significant positive influence on the LSD. Moreover, regional differences in the human disturbance of nature intensify the spatial variation of LSD. To quantify the intensity of human disturbance to nature, a human-nature conflict index (HNCI) is constructed by quantifying the difference between the slope distributions of artificial and natural landscapes. The results show that in the middle section of the YRB, humans are developing more steep mountainous areas, leading to more dense landslides. This study provides a reference for landslide risk management and land use planning in the YRB.

Związek między wzorem krajobrazu a zakłóceniami powodowanymi przez człowieka w latach 1990-2018 w Portugalii kontynentalnej

The land use/land cover pattern of landscapes as the main element of the landscape structure has an important role in landscape management, nature conservation, and preservation, considering its ability to provide valuable information about the spatial distribution and changes in land cover that occur on the Earth's surface. On the other hand, human activities have caused significant impacts on ecosystems, resulting in a loss of biodiversity, increased risks of erosion and soil degradation, and wildfires. In the last few decades, the growing trend of occurrence of negative effects on land use/land cover has not contributed to the achievement of sustainable development goals (SDGs), considering that the relationship between humankind and the environment is an extremely fragile equilibrium. In recent decades, large-scale land use and land cover (LULC) patterns have shown stability, but there have been significant dynamics observed specifically in forest areas and agricultural land. Among these changes, the conversion of maritime pine to eucalyptus stands out as the most relevant transition in terms of forest and agroforestry use classes. This conversion is a result of economic incentives available, which have contributed to the gain in forested areas. This study intends to verify how the alteration of the landscape configuration, represented by different metrics of configuration and diversity, is related to the intensity of human disturbance. The objectives of the study are: (1) to quantify the change in land use/land cover (LULC) patterns and the degree of human disturbance in Mainland Portugal between 1990 and 2018, and (2) to study the relationship between LULC configuration and the impact resulting from human disturbance under different levels of intensity, to understand how changing trends in landscape pattern can serve as indicators to estimate landscape changes resulting from human actions. The Hemeroby index (HI) was calculated to quantify the impacts on ecosystems resulting from disturbance caused by human actions. Based on the Hemeroby index value analysis for the period between 1990 and 2018, the level of naturalness increased in 58% of the country, mainly in the south and east of Portugal. The landscape pattern was quantified using a set of metrics, namely Mean Patch Size (MPS), Mean Shape Index (MSI), Total Edge (TE), Mean Patch Fractal Dimension (MPFD), and Mean Perimeter-Area Ratio (MPAR). To identify the existing statistical correlations between the geometric parameters of the landscape and the HIs values, the Spearman method was used. At the landscape level, the metrics TE and MSI have a strong negative correlation with HI. This suggests that landscapes with greater structural complexity are good indicators of low levels of hemeroby. At the class level, edge density (ED) and mean patch size (MPS) showed a significant correlation with the Hemeroby index for seminatural areas (all metrics), artificial surfaces and forests (TE, MSI, and MPS), agricultural areas (TE, MPS, and MPFD), and Bare Ground (TE, MSI, and MPFD).

Relationship between Landscape Pattern and Human Disturbance in Serbia from 2000 to 2018

This study intends to verify how the alteration of the landscape configuration, represented by different metrics of configuration and diversity, is related to the intensity of human disturbance. The objectives of the study are: (1) to quantify the change in land use/land cover (LULC) patterns and the degree of human disturbance in Serbia between 2000 and 2018, and (2) to study the relationship between LULC configuration and the impact resulting from human disturbance under different levels of intensity, to understand how changing trends in landscape pattern can serve as indicators to estimate landscape changes resulting from human actions. The Hemeroby Index (HI) was calculated to quantify the impacts on ecosystems resulting from disturbance caused by human actions. Based on the analysis of the variation in the value corresponding to the HI for the period between 2000 and 2018, the level of naturalness increased by only 5% of the territory of Serbia, with this change being verified mainly in SE Serbia. The landscape pattern was quantified using a set of LULC metrics. We used the Spearman method to identify the existing statistical correlations between the geometric parameters of the landscape and the HIs values. At the landscape level, the Mean Shape Index, Edge Density, Mean Patch Fractal Dimension, and Shannon Diversity Index show a strong negative correlation with HI. This correlation suggests that landscapes with greater structural complexity are good indicators of low levels of hemeroby. At the class level, Edge Density and Mean Patch Size correlate significantly with the HI for artificial surfaces, agricultural areas, forests, and semi-natural areas.

Assessment of ecosystem stability in the agro-pastoral transitional zone for local sustainable management: A case study in Duolun County, northern China

Assessing the ecosystem stability and the influencing factors in the fragile ecosystem of the agro-pastoral transitional zone of Northern China (APTZNC) is essential for the sustainable provision of multiple ecosystem services and adaptive ecosystem management. In this study, we selected Duolun County in the APTZNC as the study area. The ecosystem stability was assessed in terms of resistance and resilience, and the factors influencing the spatial distribution of stability were explored. The results showed that the mean value of ecosystem resistance in the study area was 0.61 (at a medium–high level), while the mean values of resilience and stability were 0.38 and 0.36, respectively, (at a medium–low level) in the past 21 years. The spatial patterns of ecosystem resistance, resilience, and stability showed significant spatial heterogeneity. Temperature and elevation were both negatively correlated with ecosystem resistance. At the same time, human activities and socioeconomics are the key factors which influence the distribution of stability indicators. The population density and gross domestic product show a correlation with stability, and the stability also varies across different land uses. Forest ecosystems showed high stability compared to croplands and grasslands when exposed to the same climate change perturbations; cropland ecosystems with a high intensity of human disturbance showed a loss of stability, while grassland ecosystems showed a gradual improvement in stability. These findings can provide effective information for sustainable management of different regions or ecosystem types in the context of climate change and intensified human activities.

Spatial correlation analysis between human disturbance intensity (HDI) and ecosystem services value (ESV) in the Chengdu-Chongqing urban agglomeration

The spatial correlation between human disturbances and ecosystem services carries profound implications, serving as a pivotal tool for quantifying the magnitude of human impacts on ecosystems and offering invaluable insights for the development of effective management and conservation strategies. This research endeavors to conduct an exhaustive analysis of the spatial patterns between human disturbance intensity and ecosystem services in the Chengdu-Chongqing urban agglomeration, as well as to explore the spatial associations between these two factors. In the paper, we conducted a comprehensive analysis of five key indicators of human pressure, namely population density, gross domestic product (GDP), land use type, transportation network and energy consumption. These indicators were carefully examined and utilized to create a spatial map depicting the integrated human disturbance intensity index in the Chengdu-Chongqing urban agglomeration area in the year 2020. Concurrently, we utilized the ESV equivalent factor method to estimate the ecosystem service value (ESV). Bivariate Local Moran Index and spatial autocorrelation analysis were introduced to quantitatively depict and visualize the spatial relationship between human disturbance and ecosystem services. This research provides valuable insights into the intricate patterns of human pressures and ecosystem services in urban agglomeration scale. The key findings are as follows. First, the integrated human disturbance intensity is relatively high in the hub parts of Chengdu, Chongqing, and Deyang, as well as the middle zone of the cities between Chongqing and Chengdu. Second, the high value of supply services is distributed in the periphery of the cities, while the value of supply services in the middle of the cities tends to be medium and low. The majority area in the middle of the entire study area has low and medium–low values of regulation and maintenance service. At the fringes, there are only a few cities with higher values, including Ya'an, Leshan, Deyang and the eastern part of Chongqing. The distribution of cultural service values is quite similar to the distribution of regulation and maintenance service values, with the low value areas being very large and located in the middle of the study area, while the high value areas are significantly smaller and scattered around the perimeter of the study area. Third, the global Moran's index of cumulative human disturbance is 0.798, indicating that human disturbance exhibits a significant spatial autocorrelation. The global Moran's index of ecosystem services is 0.410, indicating that ecosystem services present aggregation in space as well. Fourth, the Bivariate Moran′s I between human disturbance and supply services is −0.221. The Bivariate Moran′s I between human disturbance and regulation and maintenance service is −0.212. And the Bivariate Moran′s I between human disturbance and cultural services is −0.462, which shows a stronger negative correlation.

Urbanization and land use regulate soil vulnerability to antibiotic contamination in urban green spaces

The presence of antibiotics in environment is an emerging concern because of their ubiquitous occurrence, adverse eco-toxicological effects, and promotion of widespread antibiotic resistance. Urban soil, which plays a noticeable role in human health, may be a reservoir of antibiotics because of intensive human disturbance. However, little is understood about the vulnerability of soil to antibiotic contamination in urban areas and the spatial–temporal characteristics of anthropogenic and environmental pressures. In this study, we developed a framework for the dynamic assessment of soil vulnerability to antibiotic contamination in urban green spaces, combining antibiotic release, exposure, and consequence layers. According to the results, soil vulnerability risks shown obvious spatial–temporal variation in urban areas. Areas at a high risk of antibiotic contamination were usually found in urban centers with high population densities and in seasons with low temperature and vegetation coverage. Quinolones (e.g., ofloxacin and norfloxacin) were priority antibiotics that posed the highest vulnerability risks, followed by tetracyclines. We also confirmed the effectiveness of the vulnerability assessment by correlating soil vulnerability indexes and antibiotic residues in urban soils. Furthermore, urbanization- and land use-related parameters were shown to be critical in regulating soil vulnerability to antibiotic contamination based on sensitivity analysis. These findings have important implications for the prediction and mitigation of urban soil contamination with antibiotics and strategies to improve human health.

Transboundary Cooperation in the Tumen River Basin Is the Key to Amur Leopard (Panthera pardus) Population Recovery in the Korean Peninsula.

The interconnected forest regions along the lower Tumen River, at the Sino-North Korean border, provide critical habitats and corridors for the critically endangered Amur Leopard (Panthera pardus orientalis). In this region, there are two promising corridors for leopard movement between China and North Korea: the Jingxin-Dapanling (JD) and Mijiang (MJ) corridors. Past studies have confirmed the functionality of the JD corridor, but leopards' utilization of the MJ corridor has not yet been established or confirmed. In this study, we assessed the functionality of the MJ corridor. The study area was monitored using camera traps between May 2019 and July 2021. We also analyzed 33 environmental and vegetation factors affecting leopard survival and analyzed leopard movement. In the Mijiang area, the Amur leopard was mainly active in the region adjacent to the Northeast China Tiger and Leopard National Park and did not venture into area near the North Korean border. The complex forest structure allowed leopards to move into the Mijiang area. However, the high intensity of human disturbance and manufactured physical barriers restricted further southward movement. Therefore, human-induced disturbances such as grazing, mining, farming, logging, and infrastructure development must be halted and reversed to make the Mijiang region a functional corridor for the Amur leopard to reach the North Korean forest. This necessitates inter-governmental and international cooperation and is essential for the long-term survival of the Amur leopard.

Dissolved Inorganic Nutrient Biogeochemistry in an Urbanized Coastal Region: A Study of Dapeng Cove, Shenzhen

Dissolved inorganic nutrients are pivotal in maintaining the material and energy balance of marine ecosystems, impacting the survival and dynamic succession of marine organisms. To gain a deeper understanding of the source and sink characteristics of dissolved inorganic nutrients in bays affected by human activities and to elucidate the processes involving filter-feeding shellfish in relation to these nutrients, this study investigated the source and sink dynamics of dissolved inorganic nutrients in the Dapeng Cove sea area of Shenzhen. Over the past decade, a significant change in the N/P ratio within the survey area has been observed, suggesting a shift in nutrient limitation from nitrogen to phosphorus or phosphorus–silicon limitation. This induced change in the N/P ratio, along with Si/N and Si/P ratios, may facilitate the growth of cyanobacteria and, subsequently, alter the proportions of diatoms, dinoflagellates, and cyanobacteria. Seasonal fluctuations in human disturbance intensity and precipitation determine the seasonal and spatial distribution of nutrients in the bay, thereby influencing the bay ecosystem metabolism. The Land–Ocean Interactions in the Coastal Zone (LOICZ) model analysis revealed that the bay represents a major source of inorganic nitrogen and a source of phosphate in spring, summer, and autumn, while acting as a sink for phosphate in winter. Furthermore, rivers and groundwater represent the primary sources of phosphate and inorganic nitrogen in the bay. The bay exhibits an annual net ecosystem metabolic rate of 7.06 mmol C/m2/d, with denitrification dominating the nitrogen cycle at 12.65 mmol C/m2/d. Overall, the Dapeng Cove ecosystem displays net production exceeding respiration, classifying it as an autotrophic system. Additionally, the nitrogen cycle in the sea area is predominantly driven by denitrification. The analysis also revealed that the impact of oyster proliferation on the physical and chemical factors in the surveyed area is relatively weaker than that of surface runoff and groundwater inputs.

Rebound of surface and terrestrial water resources in Mongolian plateau following sustained depletion

Water resources have always played an important role in ensuring industrial and agricultural production, as well as maintaining ecosystem security in the Mongolian Plateau (MP), a typical arid to semi-arid region. Previous studies have reported the considerable shrinkages of surface water bodies affected by intense human disturbance in the MP before 2010. However, it is still unclear about the effects of those key ecological restoration efforts (e.g., the construction of ecological civilization since 2012) on water resources in the recent decade. Here, using all the available Landsat-5/7/8 surface reflectance observations, a robust water mapping algorithm based on spectral indices and thresholds, and the Google Earth Engine (GEE) cloud computing platform, we examined the changes in surface water area (SWA) in the MP during 1991–2021. In addition, based on the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) Mascon data products, we investigated the inter-annual variability and trends of terrestrial water storage (TWS) from 2002 to 2021. We found that SWA experienced remarkable increases (85.5 km2/yr) since 2009 after continuous shrinkage of surface water bodies (-205.9 km2/yr) for over 20 years, in which Inner Mongolia played a dominant role in the recovery of SWA (72.2 km2/yr). Also, TWS had undergone continuous decline before 2012 and fluctuating rebound after that. The most significant recovery of TWS mainly happened in the northern part of the MP. Quantitative attribution analyses showed that the key ecological restoration projects in China, especially the construction of ecological civilization since 2012, were the major drivers for the recovery of surface and terrestrial water resources. While previous studies reported the considerable decline of surface water resources induced by human activities in the MP since the 1990s, our research provided gratifying satellite evidence for the significant recoveries of surface and terrestrial water resources in the plateau during the past decade under the influence of ecological restoration efforts.

Effects of the urban environment on the developmental stability, size and body condition of dice snakes (Natrix tessellata) living in artificial lakeside habitats

The expansion of urban areas leads to a decrease in natural habitats, resulting some species to live in urban environments. Novel environmental factors might influence their size, body condition and development stability. The environmentally induced developmental instability can be indicated by fluctuating symmetry, which means random deviations from perfect symmetry in bilaterally symmetric creatures.Our research aimed to explore the impact of various urbanization factors on snake populations within urban habitats. To achieve this, we examined how dice snake (Natrix tessellata) populations differ in their asymmetry, body condition and size in a lake characterized by highly modified lakeside habitats, intensive urban land use, and severe human disturbance. The average size, body condition and two asymmetry indices were determined for 25 dice snake populations around Lake Balaton in Hungary. The impacts of the urban environment were characterized by land use and local variables, and the risk of road kill was also estimated.Populations living in areas with a more intensive road network or near a main road showed more asymmetric traits. It is conceivable that pollutants from vehicle traffic lead to developmental disorders that manifest themselves in more asymmetric individuals. In addition, the body condition of snakes was negatively correlated with the area of the harbours, possibly due to the intensive boat traffic and human disturbance. Finally, populations living in more urbanized areas had larger body sizes meaning that despite its negative effects through pollution, anthropized areas can provide a suitable habitat for dice snakes.While urban artificial surroundings can function as suitable habitats, our results confirm that urban environmental factors have negative effects on dice snakes. Our findings indicate that the density of road networks and the proximity of roads have adverse effects on the developmental stability of urban snakes. This underscores the need to implement conservation actions to mitigate the negative effects of roads on biodiversity.

Как совместить охрану природы и рекреационную деятельность в Арк­тике: пример природного парка «Териберка» (Мурманская область)

The authors give ecological arguments for the creation of the Teriberka Nature Park (2,418.5 ha). The Nature Park is characterized by high recreational potential as well as environmental significance. 18 species of plants and animals listed in the Red Data Book of the Murmansk Region, as well as five ones listed in the Red Data Book of the Russian Federation are recorded within the boundaries of the Natural Park. There are natural-territorial complexes of special aesthetic value here: the valley of the Teriberka River, the coast of the Barents Sea with a rugged coastline, beaches and sea terraces formed by large rounded boulders, Batareisky Waterfall, rocky hills and areas of shrub tundra, interspersed with small lakes, sheer cliffs with colonies sea birds, a number of historical and archaeological sites. Currently, the landscapes of lower reaches of the Teriberka River are experiencing a strong human impact. An important feature of the territory is easy transport accessibility for tourists. At present, the uncontrolled tourist flow is the most significant agent of the territory transformation, as a result of which landscapes with high aesthetic qualities begin to degrade. With the creation of a natural park, the intensity and coverage of human disturbances of landscapes will be reduced, and the existing aesthetic potential of landscapes will be used more efficiently. Land use planning has been developed in order to establish a differentiated regime of special protection. The nature protection areas are intended to preserve the environment in its natural state, and the recreational zone is intended to ensure and implement recreational activities and nature-educational tourism. In order to preserve the landscape and architectural unity of the village and the natural park, regulation has been introduced for the construction of new and reconstructed buildings in accordance with the historical environment.

Sedimentary macrophyte δ13Ccellulose record of environmental evolution over the past century in East Taihu Lake, China

At present, East Taihu Lake has been profoundly affected by human interventions. However, the earlier limnological conditions such as the occurrence of temporal nodes and the cause of eutrophication remain unclear due to the short temporal range covered by the instrumental record. The stable carbon isotope ratio of plant residue α-cellulose (δ13Ccellulose) is a sensitive proxy indicator of palaeoproductivity, but this proxy index is rarely used in Chinese lakes. In order to test whether δ13Ccellulose can be used as a lake ecological environment changes indicator, we investigated the relationship between the δ13Ccellulose and several geochemical proxies from a ∼ 30 cm core extending 100 years obtained from a shallow lake: East Taihu Lake, China. Here, the changes in δ13Ccellulose of plant residues in sediments from East Taihu Lake were coupled analysis with geochemistry indexes to identify the response of δ13Ccellulose from plant residues to the past environmental changes. Combined with the results of C/N ratios, δ13Ccellulose and other related studies, the big plant residues in the sediments of East Taihu Lake may be derived from autochthonous aquatic macrophytes. In addition, the δ13Ccellulose showed a significant negative correlation with total organic carbon, probably indicating the changes of primary productivity of the lake. The δ13Ccellulose and geochemical proxy records revealed that the environmental changes in East Taihu Lake have undergone three distinct periods. The first period (1900s-1960s) represented a natural state without intensive human disturbance. The acceleration of lake eutrophication from the middle period (1960s-1995s) was a consequence of intensive local human activities. The late stage (1995s-2010s) represented a minor decline in nutrient levels after the implementation of ecological protection and restoration. By comparing the results with historical documents and measurements from East Taihu Lake, we inferred that anthropogenic pressures were the primary cause of the changes in the aquatic macrophyte communities and environments. This study provides a unique approach to the ecological environment evolution of East Taihu Lake. Atpresent, Taihu Lake still suffers from annual cyanobacterial blooms due to economic growth (urbanization and industrialization). There is an urgent need for interventions to reduce nutrient inputs in order to enhance ecosystem resilience. Finally, the results of study of East Taihu Lake in China reveal the potential of combining δ13Ccellulose and other geochemical proxies to study palaeoenvironmental change, which provides new perspectives for understanding lake ecological environmental change in lakes.

Assessing the ecological impacts of opencast coal mining in Qinghai-Tibet Plateau-a case study in Muli coal field, China

Coal-based industries are critical to the contemporary world's growth, while the environmental degradation associated with the industry is also increasing. In this study, we develop the Remote Sensing Ecological Index (RSEI) and map its distribution from 2000 to 2020 using the Muli coalfield near Qinghai Lake as the research object. This index is obtained by fitting four components that are critically related to the quality of the ecological environment, including greenness, humidity, heat and dryness, to finally obtain a desirable evaluation. The results illustrate that: (1) The RSEI displayed an overall increasing trend on the time scale, but it also went through three lengthier phases of trend changes. In space view, the RSEI of the unaltered areas has greatly improved, while the damaged areas are clearly concentrated in the study area's northwestern region, where mining is common. (2) In the trend test, the overall variation of RSEI was found to be around 3%. RSEI significantly increased in 69.57% of the study region, whereas RSEI decreased dramatically in 30.43% of the study area. (3) In opencast mining disturbed areas and undisturbed areas, a different quality structure can be discovered, with Moderate and Good levels predominating in disturbed areas and Good and Excellent levels predominating in undisturbed areas. The ecological decline in damaged areas significantly hampered the overall upward trend of RSEI. (4) The Globalmoran's I value was 0.558, 0.546, 0.409, 0.574, and 0.680 in 2000, 2005, 2010, 2015, and 2020, respectively, showing a positive association between regional distribution of ecological environment quality and that opencast mining does really degrade that quality. It has been demonstrated that our evaluation accurately classify the local environment as affected by opencast mining, making it crucial for studying the relationship between coal mining and ecological quality. This index can also be utilized in the future when conducting surveys of other regions of intense human disturbance.

Human‐induced behavioural changes of global threatened terrestrial mammals

AbstractAimUnderstanding changes in the behaviour of threatened species responding to rapidly increasing human disturbances is critical for biodiversity conservation. Here, we synthesize a meta‐analysis of the cumulative effect of human disturbances on the behaviour of global threatened terrestrial mammals.LocationGlobal terrestrial ecosystem.Time PeriodData collected from 1993 to 2021.Major Taxa StudiedTerrestrial mammals.ResultsThere were significant differences in behavioural changes among categories of human disturbances (i.e. biological invasion, climate change, grazing, habitat degradation, protection management, road traffic and tourism). The effect size of road traffic on behavioural change was the largest and particularly led habitat selection to be more specialized. The effect size for habitat degradation on foraging behaviour was the largest, and the effect mainly led to a shorter time spent in foraging and a change in food selection. Changes to behaviour increased with human disturbance intensity and varied among species according to their functional traits including body mass, food habits, migration and group type. Climate change, grazing, road traffic and tourism had a greater effect on larger species. The effect size for habitat degradation on omnivorous species was the largest, while carnivorous and solitary species were more sensitive to tourism, and migratory species were especially vulnerable to climate changes.Main ConclusionsThe diverse human disturbances interact with disturbance intensity, and some species' functional traits significantly affected the behavioural change in threatened terrestrial mammals. Such behavioural changes away from predisturbance patterns may have consequences for their fitness and community interactions. The management and conservation of threatened species should incorporate knowledge of their behavioural responses to human disturbance and take into account the potential ecological consequences for biodiversity conservation.

Plant Species Composition and Diversity in Dalbergia melanoxylon Dominated Zones in Mitarure Forest Reserve in Kilwa District

The study was designed to assess the plant species composition and diversity in the Dalbergia melanoxylon dominated zone in Mitarure Forest Reserve and the nearby community forests particularly Ngea and Nambawala in Kilwa District, Tanzania. Thirty (30) circular concentric plots were established in the forest reserve and fifteen (15) plots in each of the two-community forest and used to collect vegetation data. The plant species diversity was determined using Shannon-Wiener diversity index, evenness, richness and Simpson and their indices were compared using ANOVA. Plant species diversity and evenness assessed in Mitarure Forest Reserve did not differ significantly from those from community forests. However, the plant species diversity based on Simpson index and richness were significantly higher in the Mitarure Forest Reserve compared to those in community forests. A total of 56 plant species were recorded in Mitarure forest reserve, 39 plant species in Ngea forest and 36 plant species in Nambawala forest. Mitarure forest reserve and the nearby community forests have high plant species diversity with a good stand characteristic of a typical natural forest. However, with an intensive human disturbance, the tree species composition decreases that needs an intervention through local community involvement. This strategy may contribute in the future survival of species and the natural forests in Kilwa District. Data from this study stand as baseline information for the future monitoring of the performance of stands in the natural forest ecosystem in the Dalbergia melanoxylon-dominated zones in Kilwa District.

Revisiting Vegetation Gradient Analysis and the Intermediate Disturbance Hypothesis for the Interpretation of Riverine Geomorphic Patterns

Human effects on the water economy of the river systems are currently well documented at the worldwide scale, impacting a range of ecosystem services. In this perspective article, we discuss the findings of recent papers that under different intensities of human disturbance have coupled the analyses of riverine geomorphological and plant community patterns. The discussion is carried out within the historical framework of past and current methods of sampling and analysing the river geomorphology and the plant communities along cross-sectional profiles. The research has been conducted along three major gravel-bed rivers of the south-eastern Italian Alps: Brenta, Piave, and Tagliamento. The collated and summarised results here demonstrate the existence of a strong relationship between the woody species variance that can be explained by geomorphologic patterns and human disturbance intensity. The less disturbed river has an intermediate value of species variance that can be explained by geomorphology, the intermediate-disturbed river has the highest value, and the highly disturbed river has the lowest value. Then, we proposed an interpretation key and an adaptation of the intermediate disturbance hypothesis, which reads as: “in rivers, the greatest influence of geomorphic properties on vegetation occurs in the moderate or middle ranges of a human disturbance gradient”. We argue that the “influence of the geomorphic properties on vegetation” is assessed through the species constrained variance through an ordination analysis, such as that which is explained here. The most recent collection techniques based on field survey and remote sensing are making it increasingly easy and accurate to study of the trends of geomorphic and plant community variables throughout time and space. Thus, we encourage that researchers should check whether and how our observation is conserved through different groups of taxa and intensities of natural and human disturbance.

A novel method for quantifying human disturbances: A case study of Huaihe River Basin, China.

Human disturbances have become the main factors affecting the ecological environment. Therefore, evaluating the intensity of human disturbances is of great significance for ensuring effective regional conservation and ecosystem management. In this study, we constructed a novel method to quantify human disturbances based on three components of human disturbances into three types, namely naturalness transformation, natural resource consumption, and pollutant emissions. These components were quantified using the land use naturalness index (LNI), resource consumption index (RCI), and pollution emission index (PEI). Based on these three indicators, the human disturbances index (HDI) was calculated to reflect the intensity of human disturbances. In addition, remote sensing (RS), geographic information system (GIS), and multisource data were combined in the HDI method, taking into account the temporal variability of input parameters to achieve more convenient and comprehensive dynamic monitoring and evaluation of human disturbances. The applicability and effectiveness of the HDI method were assessed in the Huaihe River Basin, China. The obtained results revealed an increase and decrease in the intensities of human disturbances in the Huaihe River Basin from 1990 to 2005 and from 2010 to 2018, respectively. In addition, areas with a high level of human disturbances in the 1990-2005 period were mainly concentrated in the agricultural and industrial areas, while those in the 2010-2018 period were mainly observed in urban areas. This change was mainly due to a decrease in the pollutant emission amounts from agricultural and industrial lands and a marked increase in resource consumption in urban areas. This study provides theoretical guidance for regional conservation in the Huaihe River Basin and a new method for quantifying human disturbances.

Flexible nest site selection of the endangered Oriental Storks (Ciconia boyciana): Trade-off from adaptive strategies

Nest site selection is a vital component of bird reproduction success, and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances. Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications. In this study, we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks (Ciconia boyciana) in different nest areas. Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas, and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas. The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks. The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain; however, nest height decreased with the abundance of food resources in the Northeast China nest area. Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies. In safer environments, nests were lower and closer to food resources, which allows parent storks to invest more in the nestlings. However, in areas where human activity was intense, nests were higher to ensure the safety of their offspring. Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting. Finally, the establishment of soft barriers around the nesting areas could increase the safety of nests.

Urban forest soils harbour distinct and more diverse communities of bacteria and fungi compared to less disturbed forest soils.

Anthropogenic changes to land use drive concomitant changes in biodiversity, including that of the soil microbiota. However, it is not clear how increasing intensity of human disturbance is reflected in the soil microbial communities. To address this issue, we used amplicon sequencing to quantify the microbiota (bacteria and fungi) in the soil of forests (n=312) experiencing four different land uses, national parks (set aside for nature conservation), managed (for forestry purposes), suburban (on the border of an urban area) and urban (fully within a town or city), which broadly represent a gradient of anthropogenic disturbance. Alpha diversity of bacteria and fungi increased with increasing levels of anthropogenic disturbance, and was thus highest in urban forest soils and lowest in the national parks. The forest soil microbial communities were structured according to the level of anthropogenic disturbance, with a clear urban signature evident in both bacteria and fungi. Despite notable differences in community composition, there was little change in the predicted functional traits of urban bacteria. By contrast, urban soils exhibited a marked loss of ectomycorrhizal fungi. Soil pH was positively correlated with the level of disturbance, and thus was the strongest predictor of variation in alpha and beta diversity of forest soil communities, indicating a role of soil alkalinity in structuring urban soil microbial communities. Hence, our study shows how the properties of urban forest soils promote an increase in microbial diversity and a change in forest soil microbiota composition.