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Exploring the impact factors associated with biodiversity and the relationship between them has always been a concerned issue in recent years. However, the previous research mostly focus on theoretical layer. Accordingly, the relationship between landscape pattern and biodiversity is to be analyzed in this research. The landscape pattern determines the function and ecological process of the landscape, and affects the species flow, information flow and energy flow in the landscape. Land use patterns has inevitably left an impact on the landscape pattern. Landscape pattern determines the function and ecological process of landscape and thus plays a significant role in biodiversity. East Dongting Lake National Nature Reserve is taken as the research object of the paper, and the remote sensing image data of three different time periods are collected, including 2000, 2010 and 2020. With an interpretation of the vegetation landscape pattern changes inside the protected area to collect and analyze the vegetation coverage. By comparing landscape patterns and the dynamic changes of land use in different periods of time, the correlation between landscape pattern characteristics and regional biodiversity is to be analyzed. Research shows: (1) From 2000 to 2020, the vegetation coverage of East Dongting Lake increased, but the landscape shape, scale, diversity and uniformity index decreased to varying degrees. (2) At the class level of landscape type, the relationship between landscape index and biodiversity is different. A complex relationship between farmland landscape and biodiversity. There is a significant positive correlation between the index of grassland landscape type and the index of regional biodiversity. (3) The correlation analysis results at the landscape level show that the landscape characteristic index is positively correlated with the regional biodiversity index. The grassland landscape in the area is the main habitat of biological species. At the same time, as the main grain producing area, the impact of farmland landscape cannot be ignored. This study has certain theoretical guiding significance for the protection and management of biodiversity in the region in terms of maintaining landscape pattern in particular the grassland landscape area and increasing vegetation coverage in the process of land use., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Wild desert grasslands are characterized by diverse habitats, uneven plant distribution, similarities among plant class, and the presence of plant shadows. However, the existing models for detecting plant species in desert grasslands exhibit low precision, require a large number of parameters, and incur high computational cost, rendering them unsuitable for deployment in plant recognition scenarios within these environments. To address these challenges, this paper proposes a lightweight and fast plant species detection system, termed YOLOv8s-KDT, tailored for complex desert grassland environments. Firstly, the model introduces a dynamic convolutional KernelWarehouse method to reduce the dimensionality of convolutional kernels and increase their number, thus achieving a better balance between parameter efficiency and representation ability. Secondly, the model incorporates triplet attention into its feature extraction network, effectively capturing the relationship between channel and spatial position and enhancing the model's feature extraction capabilities. Finally, the introduction of a dynamic detection head tackles the issue related to target detection head and attention non-uniformity, thus improving the representation of the target detection head while reducing computational cost. The experimental results demonstrate that the upgraded YOLOv8s-KDT model can rapidly and effectively identify desert grassland plants. Compared to the original model, FLOPs decreased by 50.8%, accuracy improved by 4.5%, and mAP increased by 5.6%. Currently, the YOLOv8s-KDT model is deployed in the mobile plant identification APP of Ningxia desert grassland and the fixed-point ecological information observation platform. It facilitates the investigation of desert grassland vegetation distribution across the entire Ningxia region as well as long-term observation and tracking of plant ecological information in specific areas, such as Dashuikeng, Huangji Field, and Hongsibu in Ningxia.

The decomposition rates and stoichiometric characteristics of many aquatic plants remain unclear, and our understanding of material flow and nutrient cycles within freshwater ecosystems is limited. In this study, an in-situ experiment involving 23 aquatic plants (16 native and 7 exotic species) was carried out via the litter bag method for 63 days, during which time the mass loss and nutrient content (carbon (C), nitrogen (N), and phosphorus (P)) of plants were measured. Floating-leaved plants exhibited the highest decomposition rate (0.038 ± 0.002 day -1 ), followed by submerged plants and free-floating plants (0.029 ± 0.002 day -1 ), and emergent plants had the lowest decomposition rate (0.019 ± 0.001 day -1 ). Mass loss by aquatic plants correlated with stoichiometric characteristics; the decomposition rate increased with an increasing P content and with a decreasing C content, C:N ratio, and C:P ratio. Notably, the decomposition rate of submerged exotic plants (0.044 ± 0.002 day -1 ) significantly exceeded that of native plants (0.026 ± 0.004 day -1 ), while the decomposition rate of emergent exotic plants was 55 ± 4 % higher than that of native plants. The decomposition rates of floating-leaved and free-floating plants did not significantly differ between the native and exotic species. During decomposition, emergent plants displayed an increase in C content and a decrease in N content, contrary to patterns observed in other life forms. The P content decreased for submerged (128 ± 7 %), emergent (90 ± 5 %), floating-leaved (104 ± 6 %), and free-floating plants (32 ± 6 %). Exotic plants released more C and P but accumulated more N than did native plants. In conclusion, the decomposition of aquatic plants is closely linked to litter quality and influences nutrient cycling in freshwater ecosystems. Given these findings, the invasion of the littoral zone by submerged and emergent exotic plants deserves further attention., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Plant diversity exploration needs to be accelerated because many species will go extinct before their discovery and description, and many species-rich regions remain poorly studied. However, most contemporary plant collections prefer to focus on a specific group, which hinders the exploration and conservation of plant diversity. Therefore, we need an alternative approach to the dilemma at hand. The comprehensive Natural History Collection (NHC), which existed throughout the pinnacle of biodiversity exploration in the 20th century could be considered. We explore Ernest Henry Wilson's (one of the most successful naturalists in the 20th) plant collections in China as a case to illustrate the advantages of NHC and discuss whether NHC deserves to be promoted again today. From multiple sources, we gathered 19,218 available specimen records of 11,884 collecting numbers assigned and analyzed the collected species, the collection's nature, and restored four routes of his explorations. Results reveal that Wilson's specimens were collected from 28 prefecture-level cities and 38 county-level regions of 7 provinces or municipalities, they belong to 200 families, 1046 genera, 3794 species, and 342 infraspecific taxa, approximately 41 %, 22 %, 10 %, 5 % of Chinese plant families, genera, species, and infraspecific taxa respectively. The Wilson case study shows that NHC is particularly effective in emphasizing species discovery and conservation, recording ecological information, understanding a region's flora, and developing landscape applications. Therefore, we strongly advocate for the expansion of natural history collections in species-rich regions. Furthermore, we recommend the employment of specialized collectors, the enlistment of international cooperation, and the standardization of guidelines for future NHCs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

With the increase of operation cycle in long-distance water conveyance project, the problem of silt or algae residue deposition in river channels is becoming more and more prominent, especially in the vicinity of some uncommonly used bifurcation and outflow gates along the water conveyance project. When the deposition reaches certain thickness, it will not only affect the water quality of local water bodies, but also seriously affect the normal operation of these bifurcation and outflow gates. In order to alleviate this problem, the prevention and control of algae residue deposition in long-distance water conveyance project is mainly explored from two perspectives: (1) the scouring effect on the bottom of the side channel is compared by studying different diversion ratios of the side channel; (2) The arc guide wing wall is built near the junction of the main channel and side channel. The simulation is conducted at 6 different included angles including -10°, -5°, 0°, 5°, 10° and 15°, and for non-guide wing wall. The incoming flow is simulated at 280 m 3 /s of general flow and 320 m 3 /s of design flow. A total of 14 groups of experiments are carried out for numerical simulation. It can be concluded that, when the incoming flow is held constant, a higher diversion ratio results in a more effective scouring of the bottom sediment in the side channel; when the included angles of the guide wing wall are -10°, -5°, 0° and 5°, it has a significant effect on the prevention and control of algae deposition near the junction; when the included angles of the guide wing wall are 10° and 15°, it cannot play a role in prevention and control and also hinders the normal operation of the river channel., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The plant economic spectrum can explain the trade-off strategies of vascular plants between resource acquisition and storage. Grazing can alter the plant functional characteristics of grassland ecosystems, resulting in a shift in plant resource acquisition strategies. Taking fenced grassland as a control, in this study we quantified six leaf traits and four root traits of 14 plant species (those that comprised >85 % of the species community abundance) of different grazing time grasslands in desert grasslands in Ningxia. We examined how grazing time shapes the functional structure of plant communities and the resource acquisition strategy. The results revealed an inverse pattern of the fast-slow economic spectrum of leaf and root traits; that is, as grazing time increased, the leaf traits shifted from an acquisitive type to a conservative type of resource acquisition strategy. In contrast, the root traits showed a shift from a conservative type to an acquisitive type of resource acquisition strategy. Grazing time leads to a whole plant economic spectrum, and plant functional traits may facilitate their response to environmental change, the study of which can hereby deepen our understanding of the plant economics spectrum. Our study provides new evidence that leaf and root resource acquisition and utilization are relatively independent under grazing pressure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The ecological niche gradient is an important determinant of microbial community structure. In this paper, we studied variation in rhizosphere bacterial diversity and community composition along an ecological niche gradient. We used the high-throughput sequencing of 16S rRNA genes to study changes in the rhizosphere soil microbial communities of six grass and four shrub species during the secondary succession of abandoned farmland on the Loess Plateau of China. A structural equation model (SEM) was employed to disentangle the relative contribution of ecological niche and soil properties to bacterial diversity and community composition. Proteobacteria, Acidobacteria, and Actinobacteria were the dominant phyla of rhizosphere bacteria in all samples. During the dynamics of the plant niche from low to high, bacterial community composition transitioned from Actinobacteria + Acidobacteria to Proteobacteria + Bacteroidetes higher abundance. Moreover, the bacterial diversity and species richness changed with an increasing niche gradient, showing a clear differentiation in the rhizosphere bacterial community of grassland and shrubland. Further, diversity and species richness decreased from the middle niche of B. ischaemum to the poles, indicating that the succession process had not yet reached the climax community stage. Community assembly analysis suggested that the stochastic process gradually strengthened along the increasing ecological niche gradient, especially the drift effect. Furthermore, SEM analysis showed that the ecological niche had significant negative effects on soil properties and bacterial richness, while the effects on bacterial diversity and the stochastic processes of community assembly were weakened and insignificant. Altogether, our findings suggest that the complex interaction of the ecological niche with bacterial diversity and composition was determined by soil properties. Further, bacterial diversity was not necessarily higher with increasing ecological niche gradients. [ABSTRACT FROM AUTHOR]