ARTICLE | doi:10.20944/preprints201910.0173.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: UAV remote sensing; large wild herbivore populations; grazing pressure; functional zones; Yellow-River-Source National Park
Online: 16 October 2019 (04:30:27 CEST)
Using the Yellow-River-Source National Park (YRSNP) as a study site, an unmanned aerial vehicle (UAV) remote sensing and line transect method was used to investigate the number of wild herbivorous animals and livestock, including the kiang (Equus kiang) and Tibetan gazelle (Procapra picticaudata). A downscaling algorithm was used to generate the forage yield data in YRSNP based on 30 m spatial resolution. On this basis, we estimated the forage–livestock balance, which included both wild animals and livestock, and analyzed the effects of functional zone planning in national parks on the forage–livestock balance in YRSNP. The results showed that the estimates of large herbivore population numbers in YRSNP based on population density in the aerial sample strips, which were compared and validated with statistical data and warm season survey results, indicated that the number of kiangs and Tibetan gazelles in the 2017 cold season was 12900 and 12100, respectively. The number of domestic yaks, Tibetan sheep, and horses was 53400, 76800, and 800, respectively, and the total number of sheep units was 353200. The ratio of the number of large wild herbivores and livestock sheep units was 1:5; Large wild herbivores have different preferences for functional zones, preferring ecological restoration areas consisting mainly of degraded grassland; The grazing pressure indices of the core reserve areas and ecological restoration areas were 0.168 and 0.276, respectively, indicating that these two regions still have high grazing potential. However, the grazing pressure index of the traditional utilization areas was 1.754, indicating that these grasslands are severely overloaded; After the planning and implementation of functional zones, the grazing pressure index of YRSNP was 1.967. Under this measure, the number of livestock was not reduced and the grazing pressure nearly doubled, indicating that forage–livestock conflict has become more severe.
ARTICLE | doi:10.20944/preprints202107.0424.v2
Subject: Business, Economics And Management, Econometrics And Statistics Keywords: digital inclusive finance; rural income; Henan Province, China; empirical analysis; countermeasures and suggestions
Online: 29 July 2021 (11:16:10 CEST)
This paper empirically analyzes the relationship between digital inclusive finance and rural income, and demonstrates that digital inclusive finance plays a significant role in promoting rural income, based on the 2012-2018 panel data of 17 cities in Henan Province of China. Further dimensional research unveils that all of its breadth of coverage, depth of use and degree of digitization present significant positive correlation with rural income, and a robustness test was conducted through the sub-sample method. In addition, according to regression analysis on the influencing factors of digital inclusive finance through the Tobit model, the level of economic development, the Internet popularity rate and the urbanization rate have a positive effect on the development of digital inclusive finance in Henan, while the income gap between urban and rural areas and the degree of opening up have a negative effect. Finally, predicated on the analysis of the restrictive factors of Henan’s digital inclusive finance in increasing rural income, the paper puts forward specific policy proposals based on the native state quo.
ARTICLE | doi:10.20944/preprints201703.0178.v1
Subject: Environmental And Earth Sciences, Remote Sensing Keywords: mobile laser scanning; voxel; clustering; segmentation
Online: 23 March 2017 (08:48:22 CET)
The segmentation of urban scene mobile laser scanning (MLS) data into meaningful street objects is a great challenge due to the scene complexity of street environments, especially in the vicinity of street objects such as poles and trees. This paper proposes a three-stage method for the segmentation of urban MLS data at the object level. The original unorganized point cloud is first voxelized, and all information needed is stored in the voxels. These voxels are then classified as ground and non-ground voxels. In the second stage, the whole scene is segmented into clusters by applying a density-based clustering method based on two key parameters: local density and minimum distance. In the third stage, a merging step and a re-assignment processing step are applied to address the over-segmentation problem and noise points, respectively. We tested the effectiveness of the proposed methods on two urban MLS datasets. The overall accuracies of the segmentation results for the two test sites are 98.3% and 97%, thereby validating the effectiveness of the proposed method.
ARTICLE | doi:10.20944/preprints202305.2235.v1
Subject: Environmental And Earth Sciences, Waste Management And Disposal Keywords: Biochar aging; Ca-rich biochar; Carbon stability; Farmland soil; Carbon sequestration
Online: 31 May 2023 (11:18:37 CEST)
Converting biowaste into biochar and subsequently putting it into the soil are considered to be an effective approach to sequestrate carbon (C). However, biochar will inevitably undergo the aging process in soil, which influences its stability, and ultimately threatens its carbon sequestration ability. This study selected CaCl2 as exogenous additive of sewage sludge and bone dreg to quantify both surface C and bulk C stability in Ca-rich biochars under three aging processes (dry-wet aging, freeze-thaw aging, and natural aging in farmland soil), and revealed the influence mechanisms of exogenous Ca on biochar stability. Results showed that after dry-wet aging (25 rounds), freeze-thaw aging (25 rounds), and natural aging in different farmland soils (5 months), oxidized surface C in Ca-rich biochar decreased by 10~23%, 28~41%, and 0~74%, respectively, compared to that in pristine biochar, while oxidized bulk C decreased by 6~10%, 0~1%, and 0~35%, respectively. Under three aging processes, the surface C and bulk C stability in Ca-rich biochar were superior to that in corresponding pristine biochar, which was attributed to the “protective effect” of Ca-containing crystals on biochar surface, including CaO, Ca5(PO4)3Cl, Ca5(PO4)3(OH), Ca8H2(PO4)6·H2O and Ca10(PO4)6(OH)2. These Ca-containing crystals could block the connection between biochar-C and the external oxidizing environment, intervening the oxidation of C-C/C=C in biochar, but also prevented aging from damaging C structure of biochar, reducing the generation of fragmented structure. By comprehensively assessing surface C and bulk C stability under three aging processes, final C sequestration in Ca-rich biochar increased to 27~80%, compared to that in pristine biochar (23~74%). Therefore, Ca-rich biochar is more dominant than pristine biochar, considering C sequestration potential during long-term aging in soil.
ARTICLE | doi:10.20944/preprints202309.1719.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: Pb contaminated soils; repair; soil washing; intermittent and continuous experiments
Online: 26 September 2023 (05:05:01 CEST)
Soil washing is a rapid and efficient method for heavy metals removal. In this study, in order to prove the feasibility of leaching remediation technology for remediation of lead-contaminated soil around a smelter, intermittent oscillating washing tests and extensive continuous tests were conducted to remediate Pb contaminated soils. Plant growth tests with wheat (Bainong Aikang 58) were also conducted to investigate the effects of leaching on plant growth and the Pb content of stems and leaves. The results revealed that in soils, Pb mainly exists in the forms of PbCO3, Pb5(PO4)3Cl2, PbSO4, and in small amounts of PbS. The intermittent oscillating washing tests showed that a lower liquidsolid(L/S) ratio and a higher leaching temperature and time were related to increased Pb removal efficiency. The Pb removal efficiency rates in the oscillating washing tests and the extensive continuous tests were 72.50% and 69.94%, respectively. In addition, the chemical and physical characteristics of the soil were basically unchanged after the leaching regimes. The results of the plant growth tests showed that the leaching regimes did not have a negative effect on the survival rate and growth of the wheat, and the heavy metal contents of the stem and leaf were effectively reduced. This study provides a reference for the large-scale remediation of contaminated soils.
ARTICLE | doi:10.20944/preprints202309.1586.v1
Subject: Environmental And Earth Sciences, Ecology Keywords: carbon dioxide fluxes; net ecosystem exchange; photosynthetically active radiation; salt marshes
Online: 26 September 2023 (08:19:12 CEST)
Abstract: This study observes the characteristics and influencing factors of carbon fluxes of the Momoge salt marsh ecosystem over four years, which behaves as a CO2 sink. The daily, seasonal, and interannual variations of CO2 fluxes in the Momoge salt marshes were observed using the eddy covariance method and compared with various environmental factors. An overall daily “U” shaped distribution was observed, with uptake during the day (negative values) and release at night (positive values). Annually, the carbon fluxes in the study area roughly exhibit a “V” shape. Carbon fluxes during the non-growing season predominantly showed positive values, indicating the release of CO2 into the atmosphere. Photosynthetically active radiation was the primary influencing factor affecting hourly and daytime variations in net ecosystem exchange (NEE) during the growing season, while temperature was the main factor influencing nighttime NEE dynamics. Air temperature, soil temperature, photosynthetically active radiation, precipitation, and water level all had significant impacts on daily net CO2 exchange. At the monthly scale, larger values of soil temperature, air temperature, photosynthetically active radiation, and aboveground biomass correspond to a stronger carbon absorption capacity of the ecosystem. Overall, temperature remains the primary factor for carbon fluxes in the Momoge wetlands.
ARTICLE | doi:10.20944/preprints202203.0232.v1
Subject: Chemistry And Materials Science, Surfaces, Coatings And Films Keywords: Solar steam generation; Photothermal materials; Daikon; Polydopamine; Polypyrrole
Online: 16 March 2022 (10:16:34 CET)
Interface solar steam generation (ISSG) are charming for its applications in desalination and wastewater treatment. Biomass is an attractive substrate for utilizing solar vapor evaporators because of its natural pore structure and water transportability. Polymers like polydopamine (PDA) and polypyrrole (PPy) with broadband spectrum absorption are fascinating in photothermal materials (PTMs). Herein, PDA coated daikon-based (PDA-DK) and PPy coated daikon-based (PPy-DK) PTMs have been exploited for solar steam generation. When polyethylene foam (PEF) was used as an insulating layer to limit heat loss from the PTMs to bulk water, the evaporation rate of PDA-DK and PPy-DK was raised from 0.82 kg m–2 h–1 and 0.96 kg m–2 h–1 to 1.50 kg m–2 h–1 and 1.60 kg m–2 h–1, respectively. Meanwhile, the corresponding photothermal conversion efficiency was increased to 89.01% and 98.97%, which was increased by nearly 40% under 1-sun irradiation. In addition, PDA-DK and PPy-DK exhibited remarkable stability for the solar steam generation without significant change through 15 cycles. Furthermore, PDA-DK and PPy-DK could effectively desalt seawater and purify dyeing wastewater. All the results indicate that PDA-DK and PPy-DK have great potential in real-world applications for solar steam generation.
ARTICLE | doi:10.20944/preprints201703.0112.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: Cu6Sn5 whiskers; Ag3Sn fibers; mechanical property; screw dislocation
Online: 16 March 2017 (08:50:05 CET)
Cu6Sn5 whiskers precipitated in Sn3.0Ag0.5Cu/Cu interconnection in concentrator silicon solar cells solder layer were found and investigated after reflow soldering and during aging. Ag3Sn fibers can be observed around Cu6Sn5 whiskers in the matrix microstructure, which can play an active effect on the reliability of interconnection. Different morphologies of Cu6Sn5 whiskers can be observed, and hexagonal rod structure is the main morphology of Cu6Sn5 whiskers. A hollow structure can be observed in hexagonal Cu6Sn5 whiskers, and a screw dislocation mechanism was used to represent the Cu6Sn5 growth. Based on mechanical property testing and finite element simulation, Cu6Sn5 whiskers were regarded as having a negative effect on the durability of Sn3.0Ag0.5Cu/Cu interconnection in concentrator silicon solar cells solder layer.
ARTICLE | doi:10.20944/preprints201608.0049.v2
Subject: Business, Economics And Management, Economics Keywords: mental accounting; agricultural water fee; behavioral economics; decision making; information processing; representativeness; negative psychological externalities
Online: 25 August 2016 (10:12:08 CEST)
To better understand farmers’ refusal and corresponding negative emotions to pay agricultural water fee under current policy in rural China, this paper applies mental accounting, a behavioral economics framework, to explore how the governmental policies of reform of rural taxes and fees, direct agricultural subsidy programs and agricultural water fee individually influence farmers’ decisions in paying agricultural water fee. Using fieldwork data from 577 farmers and 20 water managers in Sichuan, we explore farmers’ information processing regarding paying agricultural water fee via three sequential mental accounting processes, with the associated underlying principles and measures behind each process. We find that the information processing in three mental accounting scenarios related to the agricultural water fee elucidates farmers’ observed behaviors in rural China. Generally, in the three mental accounting scenarios, two conditional intuitive expectations and nine conditional intuitive preferences are formed, however, the conditions of those expectations or preferences cannot be matched with the facts due to the reform of rural taxes and fees, the direct agricultural subsidy programs and the internal attributes of agricultural water fee, which interpret those negative behaviors in rural China. Additionally, this paper offers a view into how previous policies create negative psychological externalities (such as farmers’ psychological dependence on the government) through mental accounting to negatively influence agents’ subsequent decision making; it highlights the significance of underlying mental factors and information processing of negative behaviors in policymaking for managing or conserving common pool resources.