Conversion Of Natural Forest Research Articles

Land-use change from native forest to avocado orchards: Effects on soil nutrient transformation and microbial communities

Land-use change is known to alter soil microbial communities and the processes they carry out. However, there is meager information about how conversion of natural forests to agricultural land for avocado production affects soil nutrient concentration and microbial activity and diversity. Total soil nutrients (C, N and P), microbial ecoenzymatic activity, and microbial diversity were studied in avocado orchards and contiguous forest fragments in Michoacán state, México. Within orchards, samples were taken from fertilized areas beneath avocado trees as well as from unfertilized areas. Results showed that (i) total phosphorus concentration was higher in avocado orchards compared to native forests soils; (ii) transformation of native forests to avocado orchards decreased the ecoenzymatic activity necessary for degradation of lignified compounds and phosphate monoesters; (iii) bacterial diversity was higher in avocado orchard soils compared to native forest soils while fungal diversity was higher in avocado unfertilized soils; (v) transformation of native forests to avocado orchards increased the evenness of bacterial and fungal communities; (vi) transformation of native forest to avocado orchards caused significant changes in the composition of soil microbial communities; however, this was clearer for fungal communities than for bacterial communities; (vii) abundance of ectomycorrhizal fungi and antagonists of plant pathogens decreased in avocado orchards while pathogenic and saprotrophic fungal guilds increased. Our results suggest that land use change from native forest to avocado orchards generates important changes in the dynamics of soil organic carbon and soil organic phosphorus in avocado orchard soils, probably due to the predominant conventional management model in the avocado belt. Furthermore, this type of land use change results in the increased abundance of important microbial groups identified as phytopathogens and the decrease of beneficial microbial groups. These changes should be taken into account to formulate forest and soil conservation polices and of more sustainable agricultural management models that consider soil microbial communities and their functions.

Forest management affects the functional traits of birds and mammals differently

AbstractForest management is an important component of global change as more than half of the world's forests are managed for human use. Although the effect of forest management on taxonomic diversity is well‐studied, we do not fully understand its impact on functional diversity. Understanding this is important to better predict how ecosystem processes will respond to global change scenarios and to implement efficient conservation actions. We conducted two large‐scale (~81 800 km2) research projects over 4 years in temperate forests of the northeastern USA to investigate how the functional structure of bird and mammal communities are affected by forest disturbance. We surveyed 85 bird species distributed in 115 sites using point counts, and 14 mammal species across 197 sites using camera traps. For each species, we selected functional traits that summarize key features of their biology, and for each site, we collected data on the level of forest disturbance based on forest loss events. We found that functional richness increased with forest disturbance for mammals but not for birds. Our results also showed that niche breadth (diet), morphological (body mass and wing length), and physiological (litter size) factors were the main determinants of the functional structure of both groups. These findings emphasize the complexity of making predictions about responses to forest management given the heavy dependence on the context and taxa studied. Overall we observed a limited response of functional diversity to forest management, which might indicate that the environmental changes generated by forest management in this region are less extreme than deforestation or conversion of natural forest to plantations of exotic species. Nonetheless, our results underscore the importance of investigating the effects of forestry on individual traits to develop strategies for managing for ecosystem functions.

Carbon Stock Dynamics in Rubber Plantations Along an Elevational Gradient in Tropical China

Carbon (C) losses due to the conversion of natural forests adversely affect the biotic and abiotic components of terrestrial ecosystems. In tropical China, rubber cultivation often extends from its traditional range to elevations of up to 1400 m. However, C stock in rubber plantations along elevation gradients is poorly understood. In this study, we investigated biomass and C stock along elevation gradients in two age groups (8- and 12-year-old) of rubber monoculture plantations in Xishuangbanna, Southwest China. The C distribution across various tree sections, ranging from aboveground biomass (AGB) to belowground biomass (BGB), including litter, big dead branches, and different soil depths were measured. A significant negative correlation was observed between AGB, BGB, litter, and total ecosystem C stocks and elevation gradients in both age groups. However, no correlation was observed between the total soil C stock and elevation gradients in 8-year-old rubber plantations, while significant decline was detected in 12-year-old rubber plantations. The highest ecosystem C stock of 197.90 Mg C ha−1 was recorded at 900 m in 8-year-old plantations; whereas, in 12-year-old rubber plantations, the highest value of 183.12 Mg C ha−1 was found at 700 m. The total ecosystem C stock decreased to their lowest level at 1000 m in both the 8-year-old and 12-year-old plantations, ranging between 113.05 Mg C ha−1 and 125.75 Mg C ha−1, respectively. Moreover, total ecosystem C stock significantly decreased from 51.55% to 8.05% and from 42.96% to 11.46% between 700 m and 1100 m, in both 8-year-old and 12-year-old plantations, respectively. Regardless of elevation gradients, the total ecosystem C stock of 12-year-old rubber plantations was 1.98% greater than that of 8-year-old rubber plantations. Biomass was the second largest contributor, while soil accounted for 82% to 90%, and the other components contributed less than 2% of the total ecosystem C stock in both age groups. These fluctuations in C stock along elevation gradients in both 8- and 12-year-old plantations suggested that rubber growth, biomass, and C stock capacity decreased above 900 m, and that age and elevation are key factors for biomass and C stock in rubber monoculture plantations.

Unintended environmental consequences of anti-corruption strategies

High agricultural profits motivate politicians to collude with local elites and ignore illegal conversion of natural forests. Fighting corruption through fiscal audits can improve local governance in general but may also unintentionally intensify such collusion and rent extraction activities within the less scrutinized forestry sector. This paper highlights such unintended consequences of a federal anti-corruption strategy in Brazil by documenting the causal effects of randomized fiscal audits on deforestation dynamics, a non-targeted outcome. Between 2003 and 2011, public audits of federal funds increased deforestation by about 10% in municipalities of the Brazilian Amazon within the first three years after the audit. The audits triggered forest loss, especially during election years, in municipalities governed by first-term mayors who managed to win re-elections afterward, and in places with a high share of cattle ranching, indicating potential collusion between local politicians and the agricultural sector.

Seed dispersal by bats (Chiroptera: Phyllostomidae) and mutualistic networks in a landscape dominated by cocoa in the Brazilian amazon

Bats play essential roles in neotropical ecosystems, performing crucial ecological functions such as insect pest control, pollination of plants with significant economic, social, and ecological value, and seed dispersal, including that of pioneer plant species. These animals are directly linked to human well-being, and declines in their populations can even have adverse effects, such as increasing the need for pesticides in regions where natural insect control is reduced. The seed dispersal conducted by bats is fundamental for maintaining neotropical biodiversity, as it supports habitat regeneration and the propagation of various plant species. Moreover, the role of these dispersers is enhanced due to their ability to inhabit a variety of environments, from natural forests to anthropized areas. However, the conversion of natural forests into agricultural production areas, as well as urbanization, has affected the structure of mutualistic networks between bats and plants. In this context, the objective of this study was to identify the pattern of seed dispersal by bats of the Phyllostomidae family in an anthropized landscape of the Brazilian Amazon. Data collection was conducted in different areas of natural forest, cocoa cultivation, and urban areas in the municipalities of the States of Pará. Regarding the results, the most representative subfamilies of bats were Carollinae (72.15 %) and Stenodermatinae (21.8 %). The botanical families Piperaceae (35.52 %) and Solanaceae (19.71 %) were the ones most preferred by the bats. Regarding species richness, the general bat-plant interaction network included 15 botanical families and 26 species of bats. The general interaction network was nested (WNODF= 29.8), with low Specialization (H2=0.27), Connectance (0.17), and Modularity corresponding to M=0.21. Thus, we highlight the importance of these species for the restoration of degraded environments. Therefore, through the execution of projects that demonstrate the importance of chiropterochory in the restoration of degraded ecosystems in the Amazon, it will be possible to create measures and subsidies focused on the conservation of bat and plant species that play a role in maintaining the planet's biodiversity.

Temporal evolution of deforestation in the Xingu River Watershed between 2008 to 2020

Anthropic activities that alter land cover patterns in Watersheds, such as deforestation, affect the food and sanitary security of the population. Thus, the objective of this study was to develop a quantitative analysis of the temporal evolution of deforestation in the Xingu River Watershed between the years 2008 and 2020. To achieve this, the methodology was organized into the following steps: Database construction (Xingu River Watershed boundaries, deforested areas, and Land Use and Land Cover); Data preprocessing; Analysis of the temporal evolution of deforestation; and Quantitative analysis of land cover change in the deforested areas. It became evident that deforestation did not exhibit a standardized behavior, due to the large proportion of deforested areas in 2008 and the abrupt reduction in 2012. Furthermore, the deforestation in 2012, 2016, and 2020 resulted in greater conversion of native forests into pasture than the regeneration of these areas. Therefore, it can be concluded that 2008 had the highest deforestation rate, due to the increase in soybean prices, and that 2012 had the lowest rates due to the implementation of environmental policies, highlighting the relationship between environmental policies and the seasonality of commodity prices with deforestation rates. It was also concluded that the main destination for the deforested areas has been pastureland for livestock, and a viable solution to identify and punish offenders, as well as support small-scale producers and recover areas devastated by deforestation, is land regularization.

Labile carbon content and nutrient availability determines microbial composition in topsoil and subsoil following land‐use change in subtropical China

AbstractEvaluating the impact of land‐use intensification on soil microbial communities is essential for recognizing the implications on microbiome stability and ecosystem function. The microbial biomass and enzyme activity in the topsoil have been found to decrease as a consequence of natural forest conversion; however, the impact of land‐use conversion on the microbes in subsoil remains largely unclear. Here, we examined the effect of primary forest conversion to plantations and cultivated lands on microbial communities at three sites with similar soil, climate, and landform. The forest conversion was set as the experimental treatment, and the primary forest as the control. A linear mixed‐effect model was applied to investigate the role of environmental parameters in shaping the soil microbial biomass and community determined by the phospholipid fatty acids analysis in both the topsoil (0–20 cm) and subsoil (20–40 cm). Compared to the primary forest, the total microbial biomass, β‐1,4‐N‐acetylglucosaminidase, leucine aminopeptidase, acid phosphatase activities, and labile organic C fraction contents in both topsoil and subsoil were reduced in cultivated lands. The ratios of gram‐positive bacteria to gram‐negative bacteria and arbuscular mycorrhizal fungi to saprotrophic fungi in subsoil decreased by 45%–53% and increased by 29%–151%, respectively, following the primary forest conversion to cultivated lands. The response ratio (the percentage of microbial and enzyme indicator response to the primary forest conversion) ranged from −80% to 140% depending on the soil depth, specific microbial group, and converted land‐use type. Microbial biomass and enzyme activity are primarily controlled by the labile organic C content and nutrients availability in both topsoil and subsoil. This study suggests that the primary forest conversion exerts an adverse effect on the microbial biomass, enzyme activity, and substrate availability in both topsoil and subsoil, highlighting the degradation of subsoil health in subtropical China.

Mammalian community responses in relation to anthropogenic disturbances and resource gradients in the shade coffee forest ecosystem of Southwestern Ethiopia

Understanding the effects of variation in resource availability and habitat disturbance on the ecology of mammals is vital for successful conservation management. In this study, we examined how human disturbances, resource availability and elevation gradients influence mammal assemblages in both managed coffee forest and natural forest of the Belete-Gera National Forest Priority Area, southwestern Ethiopia. We surveyed mammals using motion-detecting infrared camera traps in 90 locations for a total of 4142 camera days. We measured distance from main roads and settlements as disturbance factors, and distance from water sources, key grazing sites, and forest edges and woody plant diversity as resource variables. We assessed the mammal assemblages in coffee forest and natural forests using generalized linear models. Further, we used linear modelling to compare the relationships of mammal detection rates by feeding guilds and body size to resource variables. In total, we recorded 8815 videos identifying 23 different mammal species. The mammal assemblages in coffee forests were negatively associated with increasing distances from key grazing sites, water sources, and elevation. In contrast, the association with increasing distance from the road and woody plant diversity was positive. In addition, herbivores and large (25–200 kg) and very large (≥200 kg) mammals, were all negatively associated with increasing distance from the natural forest edges. With the conversion of natural forest to coffee forest and the intensification of coffee forest management, sustainable management of key grazing sites, water sources, and diverse woody plant species will be essential to the conservation of mammals. In addition, to ensure mammal conservation, adjacent natural forests around coffee forests should also be protected.

Deforestation impacts soil biodiversity and ecosystem services worldwide

Deforestation poses a global threat to biodiversity and its capacity to deliver ecosystem services. Yet, the impacts of deforestation on soil biodiversity and its associated ecosystem services remain virtually unknown. We generated a global dataset including 696 paired-site observations to investigate how native forest conversion to other land uses affects soil properties, biodiversity, and functions associated with the delivery of multiple ecosystem services. The conversion of native forests to plantations, grasslands, and croplands resulted in higher bacterial diversity and more homogeneous fungal communities dominated by pathogens and with a lower abundance of symbionts. Such conversions also resulted in significant reductions in carbon storage, nutrient cycling, and soil functional rates related to organic matter decomposition. Responses of the microbial community to deforestation, including bacterial and fungal diversity and fungal guilds, were predominantly regulated by changes in soil pH and total phosphorus. Moreover, we found that soil fungal diversity and functioning in warmer and wetter native forests is especially vulnerable to deforestation. Our work highlights that the loss of native forests to managed ecosystems poses a major global threat to the biodiversity and functioning of soils and their capacity to deliver ecosystem services.

Phosphorus speciation under long‐term crop rotation management in a tropical soil

AbstractCrop rotation and soil management practices after native tropical forest conversion may impact the dynamics of inorganic and organic phosphorus (Pi and Po) species in the soil. By combining the state‐of‐the‐art spectroscopic methods P K‐edge X‐ray absorption near edge structure (XANES), 31P liquid nuclear magnetic resonance (31P‐NMR) and chemical P fractionation, this study provides important insights on soil P speciation after conversion of native forest to cropland under distinct managements. A field trial was conducted in a weathered tropical soil to assess Pi and Po changes after conversion of native forest to cropland. The crop rotations were managed under no‐tillage (NT) or minimum tillage (MT) since 2003, and repeated annually until 2015, cropped in the fall–winter and spring seasons, followed by soybean in the summer. Soil XANES analysis in the end revealed that P was predominantly associated with ferrihydrite and hematite, suggesting that P speciation was more strongly influenced by the presence of iron(oxyhydr)oxide than by crop rotations and/or soil management. The conversion of native forest to cropland promoted the mineralization of Po species, leading to re‐adsorption in non‐labile forms and consequently worsening the P cycling in the system. To increase the labile P pools and supply crop P demand, inputs of inorganic fertilizers were required owing to the strong soil P sorption. Our results show that even conservation practices such as MT or NT and complex crop rotations are not sufficient to inhibit the impact of cropland conversion on soil P forms.

From desertification to restoration in the Brazilian semiarid region: Unveiling the potential of land restoration on soil microbial properties

Land desertification poses a significant challenge in the Brazilian semiarid region, encompassing a substantial portion of the country. Within this region, the detrimental effects of human activities, particularly unsuitable anthropic actions, have resulted in diminished vegetation cover and an accelerated rate of soil erosion. Notably, practices such as overgrazing and the conversion of native forests into pasturelands have played a pivotal role in exacerbating the process of land desertification. Ultimately, land desertification results in significant losses of soil organic matter and microbial diversity. To address this pressing issue and contribute to the existing literature, various land restoration practices, such as grazing exclusion, cover crops, and terracing, have been implemented in the Brazilian semiarid. These practices have shown promising results in terms of enhancing soil fertility and restoring microbial properties. Nonetheless, their effectiveness in improving soil microbial properties in the Brazilian semiarid region remains a subject of ongoing study. Recent advances in molecular techniques have improved our understanding of microbial communities in lands undergoing desertification and restoration. In this review, we focus on assessing the effectiveness of these restoration practices in revitalizing soil microbial properties, with a particular emphasis on the soil microbiome and its functions. Through a critical assessment of the impact of these practices on soil microbial properties, our research aims to provide valuable insights that can help mitigate the adverse effects of desertification and promote sustainable development in this ecologically sensitive region.

Dynamics of soil nitrogen availability following conversion of natural forests to various coffee cropping systems in northern Thailand

Land conversion critically affects soil physiochemical and biological properties, yet very little remains clear about the impact of forest conversion on the N pool and related microbial N transformations. Therefore, this study aimed to examine the dynamics of soil N availability following forest conversion into the different coffee cropping systems, and explore the mechanisms behind these dynamics from the microbial N transformation. Disturbed soil samples from two depths (0–20 and 20–40 cm) were collected from four land uses consisting of three different coffee cropping systems (coffee monocultures (C), coffee agroforestry (FC), coffee associated with persimmon (Diospyros kaki L.) (CH)) converted from natural forest and adjacent natural forest (F) in northern Thailand. The soil labile N pools (including ammonium (NH4+), nitrate (NO3−), inorganic N (IN), dissolved organic N (DON) contents and microbial biomass N (MBN)) were measured, as well as the soil total N (STN) content. Soil N transformation rates, including net N mineralization, nitrification, and immobilization, were determined using a laboratory incubation experiment. The results showed that the forest conversion to coffee agroforestry significantly increased soil N content by 39.83 % in topsoil, but no significant difference was observed in C and CH soils as compared to F soil (p ≤ 0.05). The three labile N forms (NH4+, NO3− and DON content) were significantly higher under the C, FC and CH soils in both depths, while the coffee monoculture decreased the MBN content. The increases in soil IN, IN/DON and NO3−/NH4+ ratios used as an N availability indicator were positively associated with an increase in the N mineralization and nitrification processes following the forest conversion. Interestingly, the N immobilization processes in the F and FC soils were significantly higher than those in the C and CH soils, which indirectly regulated a decreased nitrification rate in F and FC soils in our study. With the exception of the FC soil, the nitrification/N immobilization ratios in the C (4.95) and CH (4.08) soils were higher than those in the F (0.70) soil, indicating an increased N loss risk after forest conversion. Therefore, coffee agroforestry systems have the potential to be effective management strategies for improving soil nitrogen sequestration following forest conversion.

Quantifying Soil Complexity Using Fisher Shannon Method on 3D X-ray Computed Tomography Scans.

The conversion of native forest into agricultural land, which is common in many parts of the world, poses important questions regarding soil degradation, demanding further efforts to better understand the effect of land use change on soil functions. With the advent of 3D computed tomography techniques and computing power, new methods are becoming available to address this question. In this direction, in the current work we implement a modification of the Fisher-Shannon method, borrowed from information theory, to quantify the complexity of twelve 3D CT soil samples from a sugarcane plantation and twelve samples from a nearby native Atlantic forest in northeastern Brazil. The distinction found between the samples from the sugar plantation and the Atlantic forest site is quite pronounced. The results at the level of 91.7% accuracy were obtained considering the complexity in the Fisher-Shannon plane. Atlantic forest samples are found to be generally more complex than those from the sugar plantation.

Native forests transformed into cash crops reduced soil multi-functionality by modifying the microbial community composition and keystone species' abundance in the Jianghuai Hilly Region.

Conversion of native forest to cash crops is the predominant form of land use change in the Jianghuai Hilly Region. However, how plantations with different cash crops affect the soil multi-functionality is not well documented. In this study, we collected three kinds of cash crops soils (vegetable, orchard, and tea) and forest soil, to systematically review the relationship between soil microbial communities and soil multi-functionality. Soil multi-functionality had decreased in vegetable and orchard as compared to native forest, whereas tea plantation had no significant effects on soil multi-functionality. The results also showed that cash crop plantations decreased soil multi-functionality by shifting keystone species' abundance, for forest, vegetable, and orchard, the keystone species that were classified as module hubs in the bacterial co-occurrence network significantly negatively contributed to soil multi-functionality, but the keystone species categorized as module hubs in fungal co-occurrence network positively affected soil multi-functionality. Multiple soil properties were the drivers of the soil microbial community; thus, indicating that the altered soil properties under cash crop plantations were vital in determining microbial composition and biological processes. These results identified that sustainable management strategy in cash crop plantation needed to be developed for improving soil multi-functionality.

Converting natural forests to tea plantations reduced soil phosphorus sorption capacity in subtropical China

AbstractConverting natural forests to agricultural lands has been widespread globally due to increasing population and the demand for food. Phosphorus (P) is often applied to agricultural lands in excessive amounts which can saturate the natural P sorption capacity of the soil, leading to P leaching and subsequent off‐site water eutrophication. We studied the effect of land‐use conversion from natural forests to tea plantations on total soil P, P fractions, and P sorption capacity in subtropical China. Compared to natural forests, total soil P concentrations increased significantly in both 0–20 and 20–40 cm depths in tea plantations, indicative of the accumulation of P fertilizer. The increases in total soil P were primarily found in NaOH‐extractable inorganic P and residual P fractions in both depths, suggesting that P fertilizer was sorbed and occluded into more stable forms due to the high abundance of sorbents (i.e., iron [Fe], aluminum [Al] minerals, and clay). Across all soil samples, oxalate‐extractable Fe was the best predictor of soil maximum P sorption capacity (r = 0.94, p < 0.001). Surprisingly, the conversion from natural forests to tea plantations decreased both oxalate‐extractable Fe concentration and soil maximum P sorption capacity, hereby increasing the degree of P saturation in soils. Depletion of P sorbents (i.e., soil amorphous Fe) is likely a consequence of Fe removal through tea production and soil erosion, indicating soil degradation. Plantation soils have also shown other signs of degradation including the loss of nutrients (e.g., total soil nitrogen and oxalate‐extractable calcium) and soil organic matter. Our results demonstrate that the conversion of natural forests to tea plantations reduced the ability of the soil to sorb P by both saturating the natural P sorption capacity and depleting P sorbents. Soil degradation resulting from land‐use conversion has increased the environmental risk of P leaching loss, emphasizing the need for improved P fertilization management.

Carbon and nitrogen fractions control soil N2O emissions and related functional genes under land-use change in the tropics

Converting natural forests to managed ecosystems generally increases soil nitrous oxide (N2O) emission. However, the pattern and underlying mechanisms of N2O emissions after converting tropical forests to managed plantations remain elusive. Hence, a laboratory incubation study was investigated to determine soil N2O emissions of four land uses including forest, eucalyptus, rubber, and paddy field plantations in a tropical region of China. The effect of soil carbon (C) and nitrogen (N) fractions on soil N2O emissions and related functional genes was also estimated. We found that the conversion of natural forests to managed forests significantly decreased soil N2O emissions, but the conversion to paddy field had no effect. Soil N2O emissions were controlled by both nitrifying and denitrifying genes in tropical natural forest, but only by nitrifying genes in managed forests and by denitrifying genes in paddy field. Soil total N, extractable nitrate, particulate organic C (POC), and hydrolyzable ammonium N showed positive relationship with soil N2O emission. The easily oxidizable organic C (EOC), POC, and light fraction organic C (LFOC) had positive linear correlation with the abundance of AOA–amoA, AOB–amoA, nirK, and nirS genes. The ratios of dissolved organic C, EOC, POC, and LFOC to total N rather than soil C/N ratio control soil N2O emissions with a quadratic function relationship, and the local maximum values were 0.16, 0.22, 1.5, and 0.55, respectively. Our results provided a new evidence of the role of soil C and N fractions and their ratios in controlling soil N2O emissions and nitrifying and denitrifying genes in tropical soils.

Tropical insectivorous birds’ predation patterns that promote forest–farmland trophic connectivity for integrated top–down pest biocontrol

Although conversion of natural forest to agriculture can negatively impact biodiversity in many ways, some affected species may respond by dispersing across the forest–farmland eco-zone, thereby facilitating functional connections through food-web interactions beneficial to crop production and forestry. This study examined patterns of Lepidoptera (butterflies and moths), Hemiptera (bugs), and Coleoptera (beetles) herbivory, and insectivorous bird predation within forest-adjacent farms in western Kenya, and how these processes trophically connect the two ecosystems to promote pest biocontrol. Through δ13C and δ15N stable isotope analyses, proportions of maize, farmland legumes and forest trees in pest diets, and pest-prey in bird’s diets were estimated. Birds’ habitat associations and diet specializations’ influence on pest consumption and basal plant carbon levels in birds’ tissues were determined to evaluate birds’ pest-biocontrol potential. Maize was the mostly consumed plant especially by Lepidoptera, but forest trees were peimarily consumed by Coleoptera and Hemiptera. In turn, Lepidoptera were mainly consumed by forest-associated birds, whereas Hemiptera and Coleoptera were mostly consumed by farmland-associated birds. Thus, birds showed cross-habitat pest consumption tendencies, though diet-specialization was unimportant in predicting those tendencies. Muscicapidae (flycatchers and allies); Hirundinidae (swifts and swallows); Motacillidae (pipits and wagtails); and Ploceidae (weavers) birds showed the highest contributory potential for pest biocontrol of Lepidoptera pests, but Estrildidae (manikins and waxbills), Muscicapidae, and Malaconotidae (boubous and gonoleks) birds showed the best potential against Hemiptera and Coleoptera. Furthermore, more maize basal carbon was assimilated by forest-associated compared to farmland-associated birds, whereas most basal carbon from farmland legumes and forest trees were assimilated by farmland birds, suggesting that unlike pest-prey choice, basal plant carbon pathways to avian insectivorous consumers did not strongly mirror birds’ habitat associations. Lepidoptera and Hemiptera were potentially the most significant interhabitat trophic connector arthropods, and for birds, Muscicapidae, Ploceidae, and Estrildidae. These findings show that such functional connectivity may be enhanced through increasing structural cover elements that promote insectivorous birds’ dispersal between farmland and adjacent forests to boost their pest-regulation ecosystem service contribution. The results serve to inform effective management practices by agronomists, foresters, and land-use planners toward promoting landscape-scale-integrated pest management for sustainable agriculture and biodiversity conservation.

Lowland bamboo (Oxytenanthera abyssinica) deforestation and subsequent cultivation effects on soil physico-chemical properties in northwestern Ethiopia

In Ethiopia, bamboo thickets and woodlands play an important role in soil-water conservation and climate change mitigation in arid and semi-arid regions. However, bamboo mass flowering, rapid demographic changes and expansion of agricultural investments into bamboo dominated areas have led to deforestation and land degradation. This study assessed the effects of deforestation and subsequent cultivation on soil physical and chemical properties along a chronosequence of closely located agricultural lands with different times (1, 3, 5 and 7 years) since conversion from natural lowland bamboo forest. Soil samples (n = 90) were taken from both natural bamboo forests and adjacent agricultural lands at two soil depths (0–20 cm and 20–40 cm). Cation exchange capacity (CEC), K+, Ca2+, Mg2+ and available P varied significantly among cultivation periods and soil depth, while soil pH and Na+ varied with soil depth (P < 0.001). Soil C and total N contents (g/kg) in the 0–20 cm soil layer declined significantly and exponentially with increasing years under cultivation. Conversion of natural bamboo forest to cropland during the past seven-year period significantly increased soil pH with soil depth, while CEC declined throughout the cultivation period and with soil depth. In general, the results revealed that conversion of natural lowland bamboo forest and subsequent cultivation of the soil had negative effects on the measured soil physico-chemical properties.

Large‐scale sampling of beetle communities in Laos shows that conversion of natural forests into plantations leads to a decline in family richness and abundance

AbstractRapid economic development can pose a threat to the biodiversity of tropical countries. In Laos, this is manifested by the conversion of natural forests into plantations, even though this area is one of the biodiversity hotspots of Southeast Asia. Beetle communities can be good indicators of the impact of anthropogenic pressure on natural ecosystems. In this study, we analyzed for the first time a large‐scale inventory of Coleoptera to assess the ecological and anthropogenic drivers of beetle communities in Laos. We examined beetle communities (described at the family level) across the country, located in distinct habitat types, in order to understand the impact of the conversion of natural forest into plantations. We found that beetle abundance had declined in plantations compared to natural forests. At the same time, we observed fewer beetle families in plantations overall, but at the scale of sampling sites there was no difference in local richness compared to natural forests, suggesting a homogenization of beetle communities in anthropogenic habitats. Although results are certainly sensitive to our coarse classification of beetle specimens into families, the negative impact of the conversion of natural tropical forests into agriculture area can still be clearly demonstrated. Our findings highlight that it is possible to make use of unstructured large‐scale inventories to explore how beetle communities responds to landscape changes induced by human activities. We suggest that sampling beetle communities can be used as an ecological indicator to monitor anthropogenic impacts on tropical ecosystems.

Escaping Neobiota: Habitat use and avoidance by sloth bears in Jessore Sloth bear Sanctuary India

Global terrestrial ecosystem is threatened by several factors, such as infestation of invasive plants, which influence the habitat use by wildlife. Prosopis juliflora is such a plant species, sprawled over arid and semiarid ecosystems in India. Under this study, we assumed that intensification of P. juliflora negatively affects the habitat used by sloth bears Melursus ursinus, along with geographical, ecological and anthropogenic predictors in Jessore Sloth bear Sanctuary, Gujarat, India. To inquire so, we conducted sign surveys (1 km trail length in each grid) in three seasons, i.e., winter, summer and monsoon. Further, the presence/absence of species’ signs was logistically modelled with elevation, terrain ruggedness, area proportions of dense forest, open scrub, P. juliflora infested area and human encroachment with respect to the seasons. We found that the area proportion of P. juliflora negatively affects habitat use by sloth bears, while elevation, terrain ruggedness, and area proportions of dense forest and open scrub positively trigger. The proportion of encroachment varied between the seasons. Further, we inferred the human-sloth bear encounter probability from the seasonal models. During summer, followed by winter, we evidenced the relatively high probability of bear occurrence around settlements, which can be advocated by the availability of food items around villages. The current study supports the prescribed ecology of sloth bears in semiarid regions in the Indian subcontinent. The study recommends the appropriate urgent management to arrest the conversion of native forest and scrub covers to P. juliflora dominant cover, thereby avoiding probabilistic human-sloth bear encounters.