Search Results (762)

FTIR spectroscopy, attenuated total reflection (ATR), and diffuse reflectance (DRIFT) modalities, along with ICP–AES spectroscopy and correlation analysis, including two-dimensional correlation spectroscopy (2DCOS), were used for the detailed analysis of Kastanozem (chestnut) soils. Microaggregates (20–200 μm) and macroaggregates (200–1000 μm) of characteristic horizons of uncultivated (fallow) and cultivated (arable land) chestnut soils of the same origin were physically fractionated by wet sieving. The combination of these molecular and atomic spectroscopy techniques in combination with correlation analysis was able to find direct correlations between matrix-forming anions and soil organic matter (SOM) of Kastanozems. Humic substances were separated from the corresponding soil samples to reveal SOM contributions more explicitly. Microaggregates of the size fractions of 20–40 μm and 40–60 μm bore the most comprehensive information for both techniques used. Most significant differences between land-use Kastanozem samples were observed in topsoil horizons (arable P versus light-colored humic AJ horizon), and for the next pair of horizons along the profile xerometamorphic BMK horizon to structural metamorphic BM horizon. These differences included carbonate matrix and SOM amounts and composition. Topsoil arable land showed significantly smaller amounts of total organic carbon and a decrease in the share of long-chain hydrocarbons compared to fallow, which has a more distinctive character compared to similar land-use samples of Chernozem. An increase in carbonate contents with soil depth was found for both land-use samples, while the amounts and composition of the silicate matrix remained largely unchanged within the depth profile. The heterospectral 2DCOS comparison of FTIR (between horizons and land-use samples), ICP–AES (between land-use samples), and FTIR–AES (for the same sample) showed the possibility of a more reliable attribution of FTIR absorption bands and revealed the differences in the macro- and micro-aggregate elemental and SOM composition of Kastanozems. Full article

Fungi are a critical component of microbial biomass in agricultural soils, but their distribution across soil depths under different cover crops remains poorly understood. We used high-throughput sequencing of fungal ITS1 amplicons to characterize fungal communities across four soils depths (0–2, 2–4, 4–10, and 10–20 cm) in experimental field plots under four cover crop treatments: winter fallow reference (REF), cereal rye (CRYE), wild pennycress (WPEN), and a mixture of pea, crimson clover, radish, and oat (PCRO). There was no significant interaction between soil depth and cover crop treatment on both alpha diversity and beta diversity. CRYE and PCRO cover crops had low abundance of Fusarium, a genus including many important plant pathogens, and different fungal community composition relative to REF. Fungal diversity was significantly higher at 4–10 cm compared to 0–2 cm depth, but fungal richness was not affected by soil depth. Fungal community composition differed significantly between 0–4 and 10–20 cm soil depths. The relative abundance of Mortierella and unclassified Basidiomycota increased with increasing soil depth while that of Calvatia, Cryptococcus, Fusarium, and Idriella decreased with increasing soil depth. Most fungal taxa were assigned to more than one guild, but the few taxa that were classified as strict saprophytes decreased with increasing soil depth while those classified as strict symbionts increased with increasing soil depth. These differences were associated with low pH and high content of OM, K, S, P, and Zn in the topsoil layer compared to the deeper soil layer. The findings may inform the development of targeted soil management practices to promote beneficial fungi, but additional studies covering multiple study sites and sampling dates are needed for clarity. Full article

Rice paddy fields (referred to below as rice fields) are important not only for food production, but also as habitats for various species. The Nagoya Daruma Pond Frog (Pelophylax porosus brevipodus) is an endangered frog species endemic to Japan, mainly living in and around rice field areas. In July 2018, heavy rainfall caused severe flooding in Mabi Town of Okayama Prefecture, western Japan, submerging numerous rice fields and affecting local frog populations, including P. porosus brevipodus. To clarify whether the population structure of P. porosus brevipodus changed following the flood disaster in the rice fields of Mabi Town, we conducted quantitative field surveys in a rice fallow field in mid-October before (2017) and after (2018, 2020–2022, excluding 2019) the flood. The number of frogs declined sharply after the 2018 flood, reaching only a few individuals by 2020, but showed a substantial recovery in 2021 following the resumption of rice cultivation, although numbers decreased again in 2022. This recovery, despite fluctuations, indicates that habitat restoration through rice farming played a key role in enabling the population to rebound. Our findings underscore the importance of maintaining and restoring rice field environments after natural disasters for the survival and long-term recovery of P. porosus brevipodus. Full article

The vegetative mycelium of Pleurotus ostreatus (oyster mushroom) exhibits the ability to reduce nematode populations. This property may be utilized in integrated management programs targeting harmful nematodes such as Heterodera schachtii, a major pest of sugar beet crops. In addition to sugar beet, many other plant species serve as hosts for this nematode; susceptible plants promote H. schachtii development and population growth. Current control strategies rely on integrated plant protection methods, including the use of tolerant cultivars, fallowing, and trap crops such as oilseed radish and white mustard. This study aimed to determine whether sugar beet cv. Janetka or nematocidal plants—oilseed radish cv. Romesa and white mustard cv. Bardena—affect the nematocidal activity of P. ostreatus mycelium when applied together. Specifically, the influence of root or seed secretions from these plants on the activity of ten P. ostreatus mycelial strains was assessed using the model nematode Caenorhabditis elegans and the target pest H. schachtii. Experiments were conducted under laboratory conditions on water agar media colonized by P. ostreatus mycelium. Seeds or root exudates of the tested plants were applied to the mycelial surface. Following incubation, nematode mobility (C. elegans) and cyst entwining by the mycelium (H. schachtii) were evaluated, along with the ability of the mycelium to produce toxocysts. The results indicate that trap plants did not significantly alter the nematocidal activity of the mycelium. However, certain mycelial strains were slightly stimulated by seed diffusates or root exudates. Oilseed radish moderately influenced the nematocidal activity of four mycelial strains against C. elegans, whereas in the case of H. schachtii, similar effects were observed with white mustard. The mycelial elimination of H. schachtii occurred through cyst entwining, which was generally more effective in the presence of plant exudates. Overall, the findings demonstrate that incorporating trap crops such as oilseed radish cv. Romesa or white mustard cv. Bardena, as green manure in crop rotation systems, does not interfere with the nematocidal activity of P. ostreatus mycelium and simultaneously may enrich the soil with nutrients. The study further confirms that P. ostreatus maintains its ability to effectively entwine and eliminate H. schachtii cysts even in the presence of sugar beet, supporting its potential role as a biological control agent. To our knowledge, this is the first experiment that integrates the activities of trap plants and sugar beet with the nematocidal effects of P. ostreatus mycelium. Full article

Co-incorporating rice straw and Chinese milk vetch (CMV) residues can enhance soil organic carbon (SOC) sequestration and productivity. However, limited information exists regarding its effects on SOC and nitrogen (N) pools as well as the sustainability of rice production in the middle and lower reaches of the Yangtze River Basin. A 3-year field experiment was conducted to assess the effects of co-incorporating rice and CMV residues into paddy soils with chemical-N reduction on SOC and total N (TN) sequestration, SOC and N fractions, grain yields and the sustainable yield index (SYI) in Ma’anshan City, Anhui Province. The treatments included winter fallow–rice rotation without or with both rice straw incorporation and fertilization, as the control (CK and WF-IF, respectively), and rice-CMV rotation with the co-incorporation of rice and CMV residues under 100%, 80%, and 70% recommended N fertilization (CMV-IF, CMV-MIF and CMV-LIF, respectively). Compared with the CK, the CMV-IF significantly increased the rice grain yield and the SYI by 82.1% and 90.4%, respectively. The SOC and TN stocks under CMV-IF were significantly enhanced by 6.3% and 26.4%, respectively, relative to the CK. The CMV-IF exhibited the highest soil active organic C (AOC) and active total N (ATN) contents, followed by CMV-MIF, CMV-LIF, WF-IF, and CK. Microbial biomass C and microbial biomass N were the primary components of soil AOC and ATN, respectively, and linked more explicitly to the SYI than other soil C and N parameters. Therefore, the co-incorporation of rice and CMV residues, coupled with 70~80% recommended N fertilization, might represent an environmentally friendly field management practice for rice production in the middle and lower reaches of the Yangtze River Basin. Full article

Chinese yam (Dioscorea polystachya) serves as both a food crop and a traditional Chinese medicine herb, yet it suffers from severe continuous cropping obstacles, typically requiring a six-year fallow period before replanting. Long-term continuous cropping changes soil properties, including the concentration of N, P, and K, as well as bacterial composition, but the overall impact of short-term continuous cropping on important soil factors such as mineral elements, enzymes, and microbial composition still remains poorly understood. To elucidate how monoculture affects soil health, we collected rhizosphere soils from D. polystachya fields under one-, two-, and three-year continuous cropping in Chenji Town, and analyzed soil properties using general chemical methods, as well as microbial composition by Illuminar high-throughput sequencing of 16S rRNA and ITS1 regions. Furthermore, the correlation between soil properties and microbial communities was examined. The results showed that soil pH, cation exchange capacity, and organic matter content increased significantly in continuous cropping soil, whereas the concentrations of soil mineral elements (N, P, K, Ca, Mg, Na, Cu, Fe, Mn, Zn, S, and Si) decreased significantly, with the concentration of available P, K, Cu, and Zn decreased by 72.8%, 64.1%, 99.3%, and 79.4%, respectively, in 3-year continuously cropped soil. Enzyme activities, including sucrase, urease, and alkaline phosphatase, also showed a decrease of more than 81%. Fungal diversity and abundance were markedly reduced with cropping duration, whereas bacterial communities showed less response. Notably, pathogenic fungi such as Dactylonectria, Neocosmospora, and Ilyonectria, along with bacteria Streptomyces, became enriched. These microbial shifts were primarily associated with soil pH, available potassium, and alkaline phosphatase. Our study demonstrates that the decline in soil fertility coupled with pathogen buildup constitutes a major cause of the continuous cropping obstacle in Chinese yams. The results provide a scientific basis for developing targeted strategies to mitigate continuous cropping obstacles in Chinese yam production. Full article

Single-season legume green manuring is widely promoted for soil fertility restoration in degraded agricultural lands, yet its effectiveness in alkaline semi-arid soils remains poorly understood. This study investigated the impact of first-year sweet clover (Melilotus officinalis (L.)) green manuring on soil microbiome structure and agrochemical properties in southern carbonate chernozem soils of Northern Kazakhstan. Using shotgun metagenomics, we analyzed microbial communities from sweet clover-amended soils, clean fallow, and virgin steppe reference sites. Contrary to expectations, sweet clover green manuring did not enhance soil nitrogen availability, with nitrate-N content (9.1 mg/kg) remaining lower than clean fallow (10.5 mg/kg), likely due to temporary immobilization during initial decomposition. While sweet clover significantly increased archaeal diversity (p = 0.01) and enriched nitrogen-cycling taxa, including Nitrospirae and Thaumarchaeota, overall microbial richness remained unchanged (ACE index, p > 0.05). Surprisingly, functional analysis revealed only five significant metabolic differences between sweet clover and fallow systems, indicating functional convergence of agricultural microbiomes regardless of management practice. Correlation analysis identified phosphorus as the master regulator of microbial metabolism (r = 1.0, p < 0.0001), while elevated pH (9.0), K₂O (>1000 mg/kg), and $\mathrm{N}{\mathrm{O}}_3^{-}$ showed strong negative correlations with essential metabolic pathways, revealing previously unrecognized nutrient toxicity thresholds. Virgin steppe maintained 69 unique metabolic pathways lost in agricultural systems, highlighting the ecological cost of cultivation. These findings demonstrate that sweet clover green manuring in alkaline steppe soils induces selective rather than comprehensive microbiome restructuring, with limited immediate benefits for soil fertility. This study provides critical insights for developing sustainable agricultural practices in the world’s extensive semi-arid regions facing similar edaphic constraints. Full article

Understanding how land tenure and socio-economic pressures shape landscape transformation is critical for sustainable management in biodiversity-rich regions. This study examines three decades (1987–2017) of land use and land cover (LU&LC) change in the Ngerenyi area of the Taita Hills, Kenya, by integrating multispectral Landsat analysis with household survey data. Harmonized pre-processing and supervised classification of four LU&LC classes, agriculture, built-up areas, high-canopy vegetation, and low-canopy vegetation, achieved overall accuracies above 80% and Kappa values exceeding 0.75. Transition modeling using the Minimum Information Loss Transition Estimation (MILTE) approach, combined with net-versus-swap metrics, revealed persistent decline and fragmentation of high-canopy vegetation, cyclical transitions between agriculture and low-canopy vegetation, and the near-irreversible expansion of built-up areas. Low-canopy vegetation exhibited the highest dynamism, reflecting both degradation from canopy loss and natural regeneration from fallowed cropland. Household surveys (n = 141) identified agricultural expansion, charcoal production, fuelwood extraction, and population growth as the dominant perceived drivers, with significant variation across tenure categories. The population in Taita Taveta County increased from 205,334 in 2009 to 340,671 in 2019, reinforcing documented pressures on land resources and woody biomass. As part of the Eastern Arc biodiversity hotspot, the landscape’s diminishing high-canopy patches underscore the importance of conserving undisturbed vegetation remnants as ecological baselines and biodiversity refuges. The findings highlight the need for tenure-sensitive, landscape-scale planning that integrates private landowners, regulates subdivision, promotes agroforestry and alternative energy options, and safeguards remaining high-canopy vegetation to enhance ecological resilience while supporting local livelihoods. Full article

Nitrogen (N) and water are key resources for crop production and improving the efficiency with which they are used remains a major global challenge in intensive cropping systems. Here, we report how crop yield, N and water use efficiency, N surplus, and economic benefits can be improved from optimized management and crop rotations. A conventional winter wheat–summer maize double cropping (CN/WM) rotation in a three-year field experiment in the North China Plain is compared with alternative optimized rotations. The first three optimized treatments were wheat–summer maize rotation with optimized N and irrigation rates, tillage and straw management (ON/WM), and partial manure substitution (ONM/WM) or biochar addition (ONB/WM); the fourth optimized treatment was winter wheat–summer maize–spring maize producing three harvests in two years (ON/WMM); and the last was spring maize incorporating green manure during the fallow season for one harvest per year (ON/GM). The results showed that the ON/WM, ONM/WM, and ONB/WM had comparable yields to CN/WM, but significantly increased N use efficiency by 19–41% and water use efficiency by 13–20% and reduced N surplus to 353–531 kg N ha⁻¹ 2yr⁻¹. From these three optimized treatments, the ONM/WM performed better, with a comprehensive evaluation index of 0.66 and the highest economic benefits. The ON/WMM and ON/GM treatments also significantly increased N and water use efficiency but resulted in relatively low crop yields and profits; nevertheless, they significantly reduced water use and are suitable for water saving cropping systems. We concluded that optimized management-combined manure with synthetic N fertilization in wheat–summer maize rotations can achieve high crop productivity, environmental, and economic benefits, which contribute to a more sustainable crop production. Full article

The growing pressure on global cropland resources has become increasingly evident. Reconciling the urgency of cropland protection with long-term food demand is crucial for achieving resilient and sustainable cropland management. Here, we develop a comprehensive agricultural dataset and a five-dimensional evaluation framework encompassing quantity, quality, structure, ecology, and sustainability. Through synergy–trade-off analysis and structural equation modeling, we elucidate the interrelationships among these dimensions and their external drivers. By projecting future cropland retention under the Shared Socioeconomic Pathways (SSPs) and integrating multi-dimensional urgency, we propose a spatially explicit framework for resilient cropland management. The results show that (1) cropland protection urgency in the Chengdu–Chongqing Economic Circle exhibits a clear spatial gradient—low in the core areas and high along the periphery, where high-urgency zones are typically characterized by fragmentation, lower quality, and weaker ecological functions. (2) Eleven biophysical and socioeconomic factors collectively explain 23–50% of the variance in cropland protection urgency, with terrain conditions and urbanization levels exerting the strongest influence on cropland quantity, structure, and sustainability. (3) Under the SSPs, the maximum cropland retention reaches 6.944 million ha, with a future fallow ratio not exceeding 6.05%, and 45.05% of cropland designated as reserve resources. (4) Cropland within core protection zones demonstrates multi-dimensional advantages but accounts for less than 5%, highlighting the need for targeted conservation strategies. By integrating cropland protection urgency with long-term food security constraints, this study proposes a multi-level, multizonal resilience management strategy that offers practical guidance for cropland-stressed regions undergoing rapid urbanization worldwide. Full article

Orchids play an important role in nature conservation and are often used for monitoring purposes. However, interpreting orchid monitoring data can be challenging for several reasons. We present here the first monitoring data of Orchis mascula subsp. speciosa from the Bohemian Waldviertel region in Austria, where this taxon is ‘endangered’. The data show a successful spread into mesotrophic grassland, which was historically arable land, and afterwards strong population fluctuations. Within ten years, the population has grown from 50 flowering individuals to more than 800. Over the next 20 years, the population fluctuated between fewer than 200 and more than 1800 flowering individuals. We discuss these observations against the background of land use changes and different management measures (i.e., ploughing, grazing, mowing, and sowing of grassland species). Furthermore, we more generally discuss the potential of European terrestrial orchids to act as ‘pioneers’ and to successfully establish in fallow land. Finally, monitoring data for Orchis mascula from six countries was compiled and interpreted, given the various biological characteristics of orchid species. Reviewed data showed complex, multifaceted patterns, which still do not allow generalized conclusions explaining population dynamics. Full article

Sugar beet (Beta vulgaris L.) is the world’s second most important source of sugar, yet its production is seriously threatened by the beet cyst nematode Heterodera schachtii. Managing this pest remains a major challenge, especially where the use of chemical nematicides is limited or prohibited, highlighting the need for sustainable biological alternatives. This study evaluated the edible fungus Pleurotus ostreatus as a potential biocontrol agent against H. schachtii. Several offspring strains derived from a wild parental isolate (Po4) were tested in both pot and field experiments. In pot trials, mycelial application to fallow soil reduced nematode populations by 46.9–71.3%, while in soils cultivated with sugar beet, reductions of 26.2–32.5% were observed. Field experiments conducted over two consecutive years confirmed the nematode-suppressive activity of the Po4 strain, with population decreases of approximately 45–48% in fallow soil and 7–21% in sugar beet plots, whereas control plots exhibited 2–3-fold increases. These consistent trends indicate that P. ostreatus mycelium effectively limits nematode proliferation under both controlled and field conditions. The findings demonstrate the potential of P. ostreatus as an environmentally sound and practical component of integrated pest management systems, offering sugar beet producers and breeding programs a novel biological approach to sustainable nematode control. Full article

Under global warming, the differences in yield, soil nutrients, and economic benefits between various planting patterns in double-cropping rice areas were compared, and the high-yield and high-efficiency planting patterns that can adapt to climate change were selected. Four planting patterns, namely rape–rice (RaR), fallow–rice (FR), Chinese milk vetch–early rice–late rice (CRR), and fallow–early rice–late rice (FRR), were investigated. Compared with FRR, the yield of early rice increased by 13.6% using the CRR rotation. CRR could increase the spikelet per panicle of early rice, thereby enhancing rice yield. The soil’s available nitrogen content demonstrated an increase under the CRR rotation when compared with FRR. The yield under RaR increased by 11.9% on average compared with FR. The RaR rotation enhanced panicles per ha, thereby increasing rice yield. RaR could increase the soil’s available nutrient content compared with FR. Compared with CRR, FRR, and FR, the net income of RaR was higher by 1031 CNY/ha, 2046 CNY/ha and 5762 CNY/ha, respectively. Comprehensively compared with the other three planting patterns, RaR could effectively improve the soil fertility of paddy fields, grain yield, and net income. RaR is a sustainable planting pattern with a high yield and high efficiency worth popularizing. In addition, under the warming climate, the growth period and sowing date of rice of RaR and FR should be appropriately extended and postponed to avoid encountering more frequent high-temperature weather. Full article

Farmland abandonment is increasingly prevalent, especially in the Central Himalaya. Precise mapping of abandoned areas is crucial for understanding their status and socioecological impacts. However, distinguishing abandoned farmland from transitional classes like fallow land and barren land is challenging without high-resolution satellite imagery and field verification. In this context, this work analyzes farmland abandonment in three ecological villages of the Nepal Himalaya using high-resolution satellite imagery and a people-to-pixel approach. First, the study villages were divided into grids based on their areas, and satellite imagery was printed for ground truthing. Second, ground truthing was conducted to identify active and abandoned farmland areas using the Field Area Measure App and satellite imagery. We measured the extent of abandoned farmland and assessed its current conditions. Third, the measured abandoned farmland shapefiles were exported for precise on-screen mapping using the Geographic Information System, alongside detailed land-cover mapping. Next, the accuracy assessment was performed using Google Earth satellite imagery, and the overall mapping accuracy was found to be 95.8%. Mapping results show that the highest areas of abandoned farmland were found in the Mountain region with 19.2% of total farmland, followed by the Hill region (12.7%) and the Tarai region (2.6%). Out of the total abandoned farmland, 49.2% is currently covered with bushes and shrubs, 42.9% with weeds and grasses, and the remaining 7.9% with woodlands. The findings emphasize the importance of integrating satellite technology with people engagement to address complex land-use challenges and offer critical insights for sustainable land management in the Nepal Himalaya and similar regions worldwide. Full article

The soil microbiome is an essential component of agroecosystems. However, managing it remains a challenge due to our limited knowledge of how various environmental factors interact and shape its spatial distribution. This study presents a hierarchical ecological model to explain the assembly of the microbiome in sloping agricultural landscapes. Through a comprehensive analysis of bacterial and fungal communities, as well as the examination of metabolic and phytopathogenic profiles across a topographic gradient, we have demonstrated that topography acts as the main filter, structuring bacterial communities. Land use, on the other hand, serves as a secondary filter, refining fungal functional guilds. Our results suggest that hydrological conditions in floodplains favor the growth of stress-tolerant bacterial communities with low diversity, dominated by Actinomycetota. Fungal communities, on the other hand, are directly influenced by land use. Long-term fallow periods lead to an enrichment of arbuscular mycorrhiza, while agroecosystems shift towards pathogenic and saprotrophic niches. Furthermore, we identify specific topographic positions that may be hotspots for phytopathogenic pressure. These hotspots are linked to certain taxa, such as Ustilaginaceae and Didymellaceae, which may pose a threat to plant health. The derived hierarchical model provides a scientific foundation for topography-aware precision agriculture. It promotes stratified management, prioritizing erosion control and soil restoration on slopes, customizing nutrient inputs in fertile floodplains, and implementing targeted phytosanitary monitoring in identified risk areas. Our research thus offers a practical framework for harnessing soil spatial variability to improve soil health and proactively manage disease risks in agricultural systems. Full article