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The rare gastrointestinal tract epithelial polyp known as a pyloric gland adenoma (PGA) is more common in elderly women and uncommon in the duodenum. There are reports of two PGA cases involving high-grade intraepithelial neoplasia. A 75-year-old man was admitted to the hospital as Patient 1 due to “epigastric distension and pain for more than 10 days”. The mucous membrane around the stomach fundus and body was thin, and an electron gastroscopy revealed a large, thick protrusion in the stomach fundus that measured about 6 cm in circumference. High-grade intraepithelial neoplasia and stomach pyloric adenoma are the pathological diagnoses. An outside hospital provided consultation for Patient 2, a 68-year-old male. Pyloric adenoma at duodenal bulb with high-grade intraepithelial neoplasia is the pathological diagnosis. The single layer of cuboidal to low columnar epithelial cells with rounded nuclei and eosinophilic cytoplasm was surrounded by densely packed glands with sporadic cystic dilatation that made up the tumor tissue. The diagnosis of PGA required the immunohistochemical labeling of MUC6. In both cases, simple surgical resection was carried out, and followed up for half a year, no recurrence.

Spatiotemporal fusion is a method of fusing high spatial resolution low temporal resolution remote sensing images and low spatial resolution high temporal resolution in order to obtain high spatiotemporal resolution remote sensing images, which can provide data support for temporal observation of fine objects, and plays an important role in the fields of Earth sciences, environmental monitoring, and so on. This article reveals an issue that is often overlooked in the field of deep learning-based spatiotemporal fusion: the discontinuity between image blocks and image blocks. This discontinuity may have an impact on the visualization of remote sensing images and subsequent applications. In this regard, this article proposes a spatially seamless stitching approach to optimize the spatiotemporal fusion model based on deep learning. By using this method, we successfully obtain high-quality fused remote sensing images with smoother transitions. The spatiotemporal fusion model used in the experiment is a generative adversarial network-based spatiotemporal fusion model (GAN-STFM) and the data are from the Beijing Gaofen-6 dataset (BJGF6). After our splicing method, the ratio of root-mean-square error (RMSE) at the splicing seam to the overall RMSE is reduced from 1.28 to 0.99, which effectively improves the continuity of the image. This new image splicing method has the potential to improve the utility of deep learning-based spatiotemporal fusion algorithms, which has application value for generating large-scale long time series remote sensing datasets with high temporal and high spatial resolution.

Alfalfa (Medicago sativa L.) grown in acidic soils is often affected by phosphorus (P) deficiency, which results in reduced mineral nutrient content and forage quality. In this context, the effects of phosphorus (P) fertiliser remain unclear. In this study, we analysed the effects of P application on mineral nutrient content and forage quality in aluminium (Al)-sensitive (Longzhong) and Al-tolerant (Trifecta) alfalfa cultivars cultivated in two acidic soil environments. Mineral nutrient content and quality were affected by genotype, soil type, and P treatment concentration (p < 0.001). In limestone soil, for Longzhong and Trifecta, the optimal potassium (K), calcium (Ca), and magnesium (Mg) contents as well as crude protein content (CP) and ether extract (EE) values were observed at 20 mg P kg−1, that of the P content was observed at 40 mg P kg−1, and the minimum neutral detergent fibre (NDF) acid detergent lignin (ADL) values were observed at 40 mg P kg−1. In yellow soil, the maximum K, Ca, Mg, and P contents in Longzhong and Trifecta were observed at 40 mg P kg−1, whereas the maximum CP, EE, and ADL values were observed at 20 mg P kg−1. Our study provides an empirically based framework for optimising alfalfa fertilisation programmes in acidic soils.

Litter and root decomposition is an important source of soil organic matter and nutrients. To ascertain the contribution of litter and root to natural grassland nutrients in rocky desertification areas, from March 2017 to January 2018, the continuous soil column method, collector method, and litter decomposition method were used to study the soil nutrients, litter and root biomass, decomposition, and nutrient release of potential, moderate, and severe rocky desertification grasslands, as well as their responses to rocky desertification. The results showed that the litter and root decomposition rate showed a trend of being first fast and then slow, and the decomposition rate of litter and root was greater than 50% after 300 days. The annual litter decomposition rates of potential, moderate, and severe rocky desertification grasslands were 69.98%, 62.14%, and 49.79%, respectively, and the annual decomposition rates of root were 73.64%, 67.61%, and 64.09%, respectively. With a deepening degree of rocky desertification, the litter and root decomposition rate decreased. The decomposition coefficients, k, of litter in potential, moderate, and severe rocky desertification grasslands were 1.128, 0.896, and 0.668, respectively, and the decomposition coefficients, k, of root were 1.152, 1.018, and 0.987, respectively. The nutrient release processes of litter and root were different, and the release mode ultimately manifests as “release”. In rocky desertification grasslands, the organic carbon (OC), total nitrogen (TN), total phosphorus (TP), and total potassium (TK) released by litter and root decomposition were 18.93–263.03 g·m−2·yr−1, 1.79–5.59 g·m−2·yr−1, 0.18–0.47 g·m−2·yr−1, and 0.66–3.70 g·m−2·yr−1, respectively. The contribution of root to soil nutrients was greater than that of litter. The degree of rocky desertification was negatively correlated with the biomass, decomposition rate, and nutrient return amount of litter and root. The results of this study provide direct field evidence and illustrate the contribution of litter and root decomposition in rocky desertification grasslands to soil nutrients.

The deteriorating soil health under continuous monoculture is commonly found across various cropping systems. This study evaluated the effects of different tillage practices (conventional tillage and no till) and species mixtures (legumes and grasses) on arbuscular mycorrhizal fungi (AMF) community properties, soil nutrients, and enzyme activity in a 3-year experiment. Compared with traditional tillage, the number of AMF species under no-till conditions was increased, with the Glomus group being dominant. Under different tillage conditions, TN (total N) and AN (available N) contents under no till were significantly higher than those under conventional tillage, while no significant differences among other nutrients were found. The activities of soil acid phosphatase (S-ACP), soil dehydrogenase (S-DHA), and soil sucrose (S-SC) under conventional tillage were significantly higher than those under no till, and the cover crop mixtures also had an exclusive advantage in yield. Soil organic matter (SOM) indicated a significant negative correlation with glomalin-related soil protein (GRSP). The increase in diversity associated with the AMF species community was strongly correlated with the increase in three enzyme activities, and AN was negatively correlated with all species. Tillage did not significantly change soil chemistry, except for AN, and the high concentration of AN led to a decrease in AMF species. The results of this study showed that no till was an effective measure for enriching soil micro-organism population. Additionally, soil AMF diversity was improved by cover crop mixtures, and microbial diversity was higher than that under monoculture cover crops. Different AMF groups responded differently to tillage and cover crop mixtures. Across all mixtures, the combination of hairy vetch (Vicia villosa R.) and ryegrass (Lolium perenne L.) performed the best.

The availability of soil phosphorus (P), a crucial nutrient influencing plant productivity and ecosystem function, is impacted by continuously increasing nitrogen (N) enrichment, which changes the soil P cycle. The effect of varying forms of N input on soil P dynamics in P-limited karst grassland ecosystems remains unclear. To address this knowledge gap, we conducted a greenhouse experiment to explore the effects of various forms of N addition [Ca(NO3)2, NH4Cl, NH4NO3, Urea] on soil P fractions in these ecosystems, applying two levels (N1: 50 mg N kg−1soil, N2: 100 mg N kg−1soil) of N input in two soils (yellow soil, limestone soil). Results indicated that P fractions in both soil types were significantly affected by N additions, with yellow soil demonstrating a higher sensitivity to these additions, and this effect was strongly modulated by the form and level of N added. High N addition, rather than low N, significantly affect the P fractions in both soil types. Specially, except for Ca(NO3)2, high N addition significantly increased the available P in both soils, following the order: Urea and NH4NO3 > NH4Cl > Ca(NO3)2, and decreased NaHCO3-Pi in both soils. High N addition also significantly reduced NaOH-Po and C.HCl-Po fractions in yellow soil. Additionally, the response of root biomass and alkaline phosphatase activity in both soils to N input paralleled the trends observed in the available P fractions. Notably, changes in soil available P were strongly correlated with plant root biomass and soil alkaline phosphatase activity. Our study highlights that the N addition form significantly influences soil P availability, which is closely tied to plant root biomass and alkaline phosphatase activity. This finding underscores the importance of considering N input form to boost soil fertility and promote sustainable agriculture.

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid beta (Aβ) plaques in the brain. Aβ1–42 is the main component of Aβ plaque, which is toxic to neuronal cells. Si nanowires (Si NWs) have the advantages of small particle size, high specific surface area, and good biocompatibility, and have potential application prospects in suppressing Aβ aggregation. In this study, we employed the vapor–liquid–solid (VLS) growth mechanism to grow Si NWs using Au nanoparticles as catalysts in a plasma-enhanced chemical vapor deposition (PECVD) system. Subsequently, these Si NWs were transferred to a phosphoric acid buffer solution (PBS). We found that Si NWs significantly reduced cell death in PC12 cells (rat adrenal pheochromocytoma cells) induced by Aβ1–42 oligomers via double staining with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and fluorescein diacetate/propyl iodide (FDA/PI). Most importantly, pre-incubated Si NWs largely prevented Aβ1–42 oligomer-induced PC12 cell death, suggesting that Si NWs exerts an anti-Aβ neuroprotective effect by inhibiting Aβ aggregation. The analysis of Fourier Transform Infrared (FTIR) results demonstrates that Si NWs reduce the toxicity of fibrils and oligomers by intervening in the formation of β-sheet structures, thereby protecting the viability of nerve cells. Our findings suggest that Si NWs may be a potential therapeutic agent for AD by protecting neuronal cells from the toxicity of Aβ1–42.

To explore the population structures and dynamics of Rhododendron shrub communities at different stages of succession in northwest Guizhou, China, this study examined the populations of Rhododendron annae and Rhododendron irroratum shrub with two different stages. A space-for-time substitution was employed to establish the diameter class/height structures, static life tables, and survival/mortality rate/disappearance rate curves of both Rhododendron populations with different orders of succession. Their structural and quantitative dynamics were analyzed, and their development trends were predicted. The results showed that, quantitatively, the populations of R. annae and R. irroratum in the two Rhododendron communities with different orders of succession were dominated by age classes one, two, and three as well as height classes i, ii, and iii. The number of Rhododendron plants at the three age classes and the three height classes accounted for 97.61–100% of the total. The quantitative dynamic indices of R. annae and R. irroratum were both greater than 0, with and without considering external interference. In terms of age class and height structures, both Rhododendron populations were expanding populations, presenting “inverted-J-shaped” and irregular pyramid patterns. There was a sufficient number of young individuals, but few or no old individuals. Both survival curves of the populations of R. annae and R. irroratum in the two Rhododendron communities with different orders of succession belonged to the Deevy-II type. In the late stage of succession, the mortality curves and disappearance curves of both Rhododendron populations in these communities presented a trend of increasing first and then decreasing with increasing age class. This result indicates that at each age class, R. annae and R. irroratum showed a trend of gradual increase after two, four, and six years. In brief, the populations of R. annae and R. irroratum have rich reserves of seedlings and saplings, but high mortality and disappearance rates. In this context, it is necessary to reduce human interference and implement targeted conservation measures to promote the natural renewal of Rhododendron populations.

Optimal fertilization is an important measure for managing cultivated grasslands, and a necessary means for maintaining the nutrient balance, yield, and quality of grassland ecosystems. This study aimed to explore the effects of organic fertilizers on the production performance and nutritional quality of cultivated grasslands in karst areas. Two types of monocultured cultivated grasslands (i.e., Medicago sativa and Dactylis glomerata) were employed as the research objects, and a randomized block design was adopted to investigate the effects of five fertilization gradients on the forage height, coverage, yield, and nutritional quality of the cultivated grasslands. According to the results, the plant height, coverage, and yield of M. sativa first presented an increasing trend, then decreased with increasing fertilization gradient, with a peak at 20–30 t/hm2 fertilization gradient. The height, coverage, and yield of D. glomerata increased gradually with increase in fertilization gradient, and peaked at 40 t/hm2. Meanwhile, the crude protein (CP) and ether extract (EE) contents of both grassland types displayed first presented an increasing trend, then decreased with increasing fertilization gradient, and peaked at 10–30 t/hm2 fertilization gradient. The neutral detergent fiber (NDF) and acidic detergent fiber (ADF) contents of M. sativa presented “N-shaped” and “M-shaped” change trends with increasing fertilization gradient, while those of D. glomerata showed “V-shaped” and “M-shaped” change trends, reaching minimum values under fertilization gradients of 30 and 20 t/hm2, respectively. Year, fertilization, and year × fertilization (Y×F) significantly affected the plant heights, coverages, dry/fresh weight ratios, and yields of M. sativa and D. glomerata. The contribution of coverage to the subordinate function of M. sativa was greatest at a fertilization gradient of 20 t/hm2. Meanwhile, the subordinate function values of the height and coverage of D. glomerata increased gradually with increasing fertilization gradient, but the difference in the subordinate function value of height was only 0.09%–0.18% under the fertilization gradient of 20–40 t/hm2. Evaluation of forage nutrition revealed 10–30 t/hm2 and 20–30 t/hm2 as the optimal organic fertilizer application rates for M. sativa and D. glomerata, respectively.

Tree base sprouting is the main reproduction and expansion mode of Rhododendron plants. By leveraging the plot survey method, the species composition, community renewal, and species diversity in three Rhododendron shrub communities in control, and before and after clearcutting (CK, D3yr, and D6yr, respectively) were studied. Moreover, the dissimilarity of Rhododendron communities in CK, D3yr and D6yr were analyzed. The results showed that there were 26 plant species belonging to 14 families and 22 genera, in 3 communities in total, with 19 species of shrub plants and 7 species of herbaceous plants. The number of species increased from 13 in CK to 23 in D3yr and then decreased to 20 in D6yr. The height and coverage of D3yr and D6yr reached 39.3% and 58.9% of that of CK, respectively. The relative height of CK, D3yr, and D6yr was 43.79%, 65.4%, and 58.54%, respectively. The coverage of D3yr and D6yr reached 60.8% and 114.70% of that of CK, respectively. The relative coverage of CK, D3yr, and D6yr was 19.05%, 83.24%, and 77.32%, respectively. The important value of Rhododendron plants in the communities increased from 0.42 in CK to 0.74 in D3yr, and then decreased to 0.67 in D6yr. The α diversity in the shrub layer of D3yr and D6yr were generally lower than those of CK except Pielou evenness index. The β diversity indicates that the similarity between CK and D3yr was lower, that between CK and D6yr was moderate, and that between D3yr and D6yr was higher. The sprouting height and coverage of Rhododendron plants was significantly correlated with age and sprouting time. The sprouting ability of Rhododendron plants increased first and then decreased with age, while the sprouting ability of Rhododendron plants with age of 10–12 years was the strongest. Clearcutting measures can improve the dominance of Rhododendron plants in the communities, promote the sprouting and renewal of Rhododendron population, and accelerate the succession rate of communities.

Forage quality is a key property of grassland ecosystems. In this study, grassland forage qualities were measured at 373 sampling sites throughout Guizhou Province in the karst mountain region of Southwest China, and the factors affecting it were explored. The forage quality level of most plant species was categorized into four levels: (1) preferred forage species; (2) desirable forage species; (3) consumed but undesirable forage species; and (4) non-consumable or toxic forage species. High temperature and precipitation appeared to facilitate the growth of preferred forage species, but limited the growth of other plants. Increasing soil pH had a positive impact on the number and biomass of preferred forage plants, but a negative influence on other plants, especially non-consumable or toxic plants. Both GDP and population density had a positive correlation with the number and biomass of preferred forage species, while such correlations for other levels of forage species tended to be negative. Grazing could lead to a decrease in the preferred forage species. Therefore, it is suggested that by focusing on soil improvement in grassland and maintaining an appropriate grazing intensity, global warming and rapid economic growth in Guizhou Province will likely contribute to increase the forage quality of karst grasslands in Southwest China.

Post-operative nausea and vomiting (PONV) is an event of multifactorial origin with an incidence of 30% in the general population. Opioids such as fentanyl are being used as adjuvant to local anesthetic for its antiemetic effect. In this context, with this study we aimed to evaluate the impact of spinal fentanyl as an adjuvant on the incidence of PONV compared with a placebo, and shivering. A systematic search of randomized controlled trials that evaluated the use of spinal fentanyl in the prevention of PONV and shivering was conducted in different databases, of which 32 studies met the inclusion criteria. A total of 2116 patients scheduled for various surgeries, including cesarean section, orthopedic surgery in the lower limb, hysterectomy, and transurethral resection of the prostate, were included in the final analysis. The meta-analysis estimated the relative risk of incidence of PONV in the first 24 hours after surgery and secondary outcomes included the shivering symptom. The use of intrathecal fentanyl was associated with lower incidence of PONV, but not statistically significant when compared to the placebo (RR: 0.74 CI95%: 0.55-1.01 P = 0.06). Subgroup analysis showed a statistically significant reduction in PONV incidences with lower doses between 10 and 15 μg (RR: 0.44 CI95%: 0.35–0.55 P < 0.00001, I2 = 0%) but not with higher doses 20–25 μg. Secondary outcomes showed a decrease in incidence with the use of fentanyl vs the placebo (RR: 0.49, CI95% 0.33-0.72 P = 0.0003). Current evidence shows that the use of spinal fentanyl decreases the incidence of PONV, an effect favored using low doses.

Introduction The use of glucocorticoid as local anesthetic adjuvant in single-injection adductor canal block (ACB) is well-documented but its effects in the presence of an indwelling catheter is unclear. The purpose of this study was to determine the impacts of one-time perineural glucocorticoid injection on continuous adductor canal block in patients undergoing total knee arthroplasty. Methods A single center retrospective study of 95 patients undergoing unilateral total knee arthroplasty (TKA) was performed. Patients were divided into three groups based on adjuvant received through ACB before continuous catheter placement: a control group with no adjuvant (N = 41), a treatment group with dexamethasone (DEX) as adjuvant (N = 33) and another treatment group with DEX/ Methylprednisolone acetate (MPA) as adjuvant (N = 21). The primary outcome was the amount of ropivacaine administered via patient controlled ACB catheter. Secondary outcomes included numeric pain score, perioperative opioid usage, immediately postoperative prosthetic knee joint active range of motion (AROM), opioid usage at 6 weeks and 3 months, length of stay and discharge disposition. Results Patients in both treatment groups demonstrated a statistically significant decrease in the requirement of self-administered ropivacaine than the control group on postoperative day (POD) 1 (pConclusion This study suggested that single dose perineural glucocorticoid injection with DEX or DEX/MPA significantly decreased the dose of local anesthetic ropivacaine infusion required through continuous ACB for TKA while maintaining comparable level of pain score and opioid consumption, and significantly more patients were discharged home.

The restoration of vegetation on coal gangue mountains has always been an area of concern, and therefore, an important area of research. Liupanshui city in Guizhou province, China, has a large number of coal gangue mountains, and for this reason, was chosen for studying vegetation succession on these sites. Vetiveria zizanioides is known to accelerate the restoration of vegetation on coal gangue mountains and to shorten community succession timeframes. Because of this, we investigated different successional stages after the planting of V. zizanioides on coal gangue mountains in the Dahe coal mine comprehensive environmental governance project area in Liupanshui city. Through field community surveys and model prediction, the effects of planted V. zizanioides on the species composition, species diversity, and community succession of gangue mountains 3, 6, 8, 10, and 13 years after planting were explored. In total, 35 plant species belonging to 17 families and 32 genera were recorded across the five different coal gangue mountains. With more time after planting, the height, coverage, density, and biomass of V. zizanioides all decreased, but increased for Miscanthus floridulus. The Simpson diversity index, Shannon–Wiener diversity index, and Pielou evenness index all first increased before decreasing over time; maximum values were recorded for the coal gangue mountain 8 years after planting of V. zizanioides. According to different similarity and dissimilarity indices, the successional stages became more similar with increasing time after planting. According to biomass fitting and prediction curves, the succession process of coal gangue mountain plant communities could be divided into a V. zizanioides community stage, a M. floridulus community stage, and a woody plant stage, that starts to approach the natural community of evergreen broad-leaved forests, with durations of 0–5.62 years, 5.62–17.48 years, and over 17.48 years, respectively.

Southwest China is an important route for invasive species. In this study, 49 invasive plants of 15 families and 41 genera were found within 373 grassland sampling sites of Guizhou Province, a typical karst mountainous region with a high invasion risk located in Southwest China. Invasive plants could be found within over 90% of the grassland sampling sites, and malignant invasive species were found in 60% of the sites. In about 30% of the sampling sites, more than one malignant species coexisted. The malignant invasive species were mainly distributed in the southwestern part of Guizhou Province. Their distribution patterns were affected by environmental and traffic factors; they preferred areas with low elevation, high temperature, high rainfall, high soil nutrient content, and traffic accessibility and could adversely affect plant cover and biomass. Conversely, seriously invasive species and other low-level invasive species had a positive or neutral effect on grassland communities. Therefore, the focus of invasive plant control measures should be on malignant invasive species. Specific control policies and practices, especially in areas with resource-rich environments and well-developed traffic networks, should be carried out to facilitate grassland ecosystem sustainability and to prevent the spread of invasive species to inland China.

It is generally predicted that global warming will stimulate primary production and lead to more carbon (C) inputs to soil. However, many studies have found that soil C does not necessarily increase with increased plant litter input. Precipitation has increased in arid central Asia, and is predicted to increase more, so we tested the effects of adding fresh organic matter (FOM) and water on soil C sequestration in an arid region in northwest China. The results suggested that added FOM quickly decomposed and had minor effects on the soil organic carbon (SOC) pool to a depth of 30 cm. Both FOM and water addition had significant effects on the soil microbial biomass. The soil microbial biomass increased with added FOM, reached a maximum, and then declined as the FOM decomposed. The FOM had a more significant stimulating effect on microbial biomass with water addition. Under the soil moisture ranges used in this experiment (21.0%-29.7%), FOM input was more important than water addition in the soil C mineralization process. We concluded that short-term FOM input into the belowground soil and water addition do not affect the SOC pool in shrubland in an arid region.

Assessing oil pollution using traditional field-based methods over large areas is difficult and expensive. Remote sensing technologies with good spatial and temporal coverage might provide an alternative for monitoring oil pollution by recording the spectral signals of plants growing in polluted soils. Total petroleum hydrocarbon concentrations of soils and the hyperspectral canopy reflectance were measured in wetlands dominated by reeds (Phragmites australis) around oil wells that have been producing oil for approximately 10 years in the Yellow River Delta, eastern China to evaluate the potential of vegetation indices and red edge parameters to estimate soil oil pollution. The detrimental effect of oil pollution on reed communities was confirmed by the evidence that the aboveground biomass decreased from 1076.5 g m(-2) to 5.3 g m(-2) with increasing total petroleum hydrocarbon concentrations ranging from 9.45 mg kg(-1) to 652 mg kg(-1). The modified chlorophyll absorption ratio index (MCARI) best estimated soil TPH concentration among 20 vegetation indices. The linear model involving MCARI had the highest coefficient of determination (R(2) = 0.73) and accuracy of prediction (RMSE = 104.2 mg kg(-1)). For other vegetation indices and red edge parameters, the R(2) and RMSE values ranged from 0.64 to 0.71 and from 120.2 mg kg(-1) to 106.8 mg kg(-1) respectively. The traditional broadband normalized difference vegetation index (NDVI), one of the broadband multispectral vegetation indices (BMVIs), produced a prediction (R(2) = 0.70 and RMSE = 110.1 mg kg(-1)) similar to that of MCARI. These results corroborated the potential of remote sensing for assessing soil oil pollution in large areas. Traditional BMVIs are still of great value in monitoring soil oil pollution when hyperspectral data are unavailable.

Climate change is generally predicted to increase net primary production, which could lead to additional C input to soil. In arid central Asia, precipitation has increased and is predicted to increase further. To assess the combined effects of these changes on soil CO2 efflux in arid land, a two factorial manipulation experiment in the shrubland of an arid region in northwest China was conducted. The experiment used a nested design with fresh organic matter and water as the two controlled parameters. It was found that both fresh organic matter and water enhanced soil respiration, and there was a synergistic effect of these two treatments on soil respiration increase. Water addition not only enhanced soil C emission, but also regulated soil C sequestration by fresh organic matter addition. The results indicated that the soil CO2 flux of the shrubland is likely to increase with climate change, and precipitation played a dominant role in regulating soil C balance in the shrubland of an arid region.

The variation of different ecosystems on the terrestrial carbon balance is predicted to be large. We investigated a typical arid region with widespread saline/alkaline soils, and evaluated soil respiration of different agricultural and natural ecosystems. Soil respiration for five ecosystems together with soil temperature, soil moisture, soil pH, soil electric conductivity and soil organic carbon content were investigated in the field. Comparing with the natural ecosystems, the mean seasonal soil respiration rates of the agricultural ecosystems were 96%-386% higher and agricultural ecosystems exhibited lower CO(2) absorption by the saline/alkaline soil. Soil temperature and moisture together explained 48%, 86%, 84%, 54% and 54% of the seasonal variations of soil respiration in the five ecosystems, respectively. There was a significant negative relationship between soil respiration and soil electrical conductivity, but a weak correlation between soil respiration and soil pH or soil organic carbon content. Our results showed that soil CO(2) emissions were significantly different among different agricultural and natural ecosystems, although we caution that this was an observational, not manipulative, study. Temperature at the soil surface and electric conductivity were the main driving factors of soil respiration across the five ecosystems. Care should be taken when converting native vegetation into cropland from the point of view of greenhouse gas emissions.