In artificially controlled pot experiments,perennial ryegrass was mixed with other leguminous plants(white clo-ver and alfalfa)and treated with lead,zinc and cadmium(337 mg·kg^(-1),648 mg·kg^(-1),and 9 mg...In artificially controlled pot experiments,perennial ryegrass was mixed with other leguminous plants(white clo-ver and alfalfa)and treated with lead,zinc and cadmium(337 mg·kg^(-1),648 mg·kg^(-1),and 9 mg·kg^(-1),respectively)to simulate compound pollution conditions.The results showed that the concentrations of heavy metals,trans-port factors,and bioconcentration factors in mixed planting of ryegrass decreased compared with those in mono-culture.Regardless of whether heavy metal pollution was introduced,mixed planting increased the aboveground and underground biomasses of ryegrass.The different mixed planting treatments had no significant impact on the chlorophyll concentration of ryegrass.The mowing time,mixed planting treatment,and heavy metal treatment had impacts on antioxidant and osmotic adjustment substances,and there were some interactions.The mixed planting treatment did not significantly affect glutathione concentration,cysteine concentration,or nonprotein thiol.Mixed planting generally increased the nitrogen and phosphorus concentrations of ryegrass while reducing the stoichiometric ratio of carbon,nitrogen,and phosphorus.These results suggest that the mixed planting of ryegrass with legumes promotes the growth of ryegrass in the presence of high concentrations of heavy metal pollution.However,it does not enhance the ability of ryegrass to remediate heavy metal pollution in the soil.展开更多
African mahogany, one of the world’s most valuable timber species is threatened by over-exploitation in natural forests and failure of plantations due to attacks by the shoot borer Hypsipyla robusta. Mixed-species pl...African mahogany, one of the world’s most valuable timber species is threatened by over-exploitation in natural forests and failure of plantations due to attacks by the shoot borer Hypsipyla robusta. Mixed-species plantations has been reported to be an effective component of integrated pest management of major pest in other crops;but there is very limited empirical data on its use for managing Hypsipyla in mahogany mixed stands in West Africa. The aim of this study was to assess the effect of mixed-species stands as management intervention, on the growth of Khaya grandifoliola and Khaya ivorensis in relation to Hypsipyla robusta attack in a 10 ha experimental plantation in the wet evergreen forest type in Ghana. Khaya grandifoliola recorded faster growth than Khaya ivorensis in this forest type though the later naturally grow in this forest type while the former is introduced from the dry forest. Two years after planting, diameter and height growth were greater in the mixed-species stand than the pure stands for K. grandifoliola and K. ivorensis. Hypsipyla damage was less in the mixed stands of both K. grandifoliola and K. ivorensis compared to the pure stands, with the 20% and 10% Khaya mixed stand recording the lowest attack in both species. It can be recommended that mixed stands of the two Khaya species at 20% or lower Khaya density might be ideal for reducing the levels of Hypsipyla attack in this type of forest.展开更多
Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and m...Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and mixed plantations of Eucalyptus camaldulensis and Cupressus lusitanica and their impact on the regeneration of woody plants in relation with light. Data on the regenerated woody plants, individual characteristics of the plantation species and light reaching under the canopies were collected using sample plots (n = 4) with a size of 20 m × 20 m for each plantation type. The result showed that, E. camaldulensis was suppressing the growth of C. lusitanica while its growth was favored when it was mixed with C. lusitanica (p < 0.05). There were no significant differences between the pure and mixed plantations in their diversity and density of undergrowth woody plants (p > 0.05). Density of plantation trees were found not having a significant relationship with diversity of species (p = 0.801). There was a significant but not direct relationship between light reached in the understory of the canopies and diversity of species in the plantations (p = 0.027). Overall, the result indicated that both the pure and the mixed plantations were favoring the recruitment of woody plants.展开更多
The numerical modeling for the cool water outfall discharge from the LNG Plant is undertaken using CORMIX to evaluate the design of diffuser for discharge. The hydrodynamic data tide and currents are used inputs to th...The numerical modeling for the cool water outfall discharge from the LNG Plant is undertaken using CORMIX to evaluate the design of diffuser for discharge. The hydrodynamic data tide and currents are used inputs to the model. It is then calibrated using monitored data. The software has been run to calculate the mixing zone and dilution patterns for various flow conditions. Model result shows that ambient condition is achieved within 64 m from the proposed outfall locations. From the results of the modeling studies it can be concluded that the proposed diffuser design and outfall locations are suitable for all tide conditions. It also shows that there is no significant impact on the marine life due to the proposed cool water discharge, beyond the small area around the discharge location, as the parameters are attaining near ambient water quality within the acceptable space and time.展开更多
[Objectives]This study was conducted to investigate the appropriate addition amounts of lactic acid bacteria and cellulase in the mixed silage of potato plants,so as to provide a basis for the rational use of potato p...[Objectives]This study was conducted to investigate the appropriate addition amounts of lactic acid bacteria and cellulase in the mixed silage of potato plants,so as to provide a basis for the rational use of potato plants.[Methods]Fresh potato(Solanum tuberosum)seedling plants,watermelon(Citrullus lanatus)plants,and melon(Cucumis melo)plants were selected as raw materials for silage,each of which was added at a ratio of 32%,and 4%of brown flour was added additionally.On this basis,an L 9(32)orthogonal experiment was designed to investigate the effects of the amount of lactic acid bacteria(10,20,30 g/kg)and the amount of cellulase(5,10,15 g/kg)on the experimental results with sensory evaluation score as an investigation index.[Results]With the increase of the amount of lactic acid bacteria and the amount of cellulase,the sensory evaluation score of silage increased,and it was the highest when the amount of lactic acid bacteria added was 20 g/kg and the amount of cellulose was 10 g/kg.With the increase of the amounts of lactic acid bacteria and cellulase added,ammonia nitrogen showed a decreasing trend,and the pH and ammonia nitrogen were the lowest when the amount of lactic acid bacteria added was 20 g/kg and the amount of cellulose was 10 g/kg.[Conclusions]This study provides a theoretical basis for the rational use of effective ingredients and nutrients in potato plants and the development of new feed resources.展开更多
Plants in the alpine zone mainly depend on the reserved food materials stored in their rhizomes for the next growing season. We investigated the effect of mixed cropping （Phaseolus vulgaris L. var. Pinto） with four ...Plants in the alpine zone mainly depend on the reserved food materials stored in their rhizomes for the next growing season. We investigated the effect of mixed cropping （Phaseolus vulgaris L. var. Pinto） with four rhizomatous medicinal plants, i.e., Angelica glauca, Arnebia benthamii, Rheum emodi and Pleurospermum angelicoides as well as three levels of water stress treatment under two conditions （shade net and open field） on macronutrients （NPK） and biochemicals （carbohydrates and protein）. The experiment was conducted by completely randomized design （CDR）. The data were analyzed with ANOVA as well as CDR. The experimental results show that in all the species shade conditions with sever water stress （SSWS） increased the level of macronutrients （NPK）. However, （N） concentration was highest under shade with mixed cropping （SMIX）. Under SMIX, carbohydrate content was highest than open field control conditions （CONT）. This investigation results demon- strate that mixed cropping of medicinal plants with Phaseolus vulgaris could be a good livelihood option in the mountainous regions of Indian Central Himalaya. And the water-stress conditions along with mixed cropping could improve the biochemical constituents in the rhizome of these species.展开更多
Impacts of the minimum purchase price policy for grain on the planting area of rice in Hubei Province were analyzed based on a mixed linear model.After the indicator system containing the minimum purchase price policy...Impacts of the minimum purchase price policy for grain on the planting area of rice in Hubei Province were analyzed based on a mixed linear model.After the indicator system containing the minimum purchase price policy and other factors influencing the planting area of rice was constructed,principal component analysis of the system was conducted,and then a mixed linear model where the planting area of rice was as the dependent variable was established.The results show that after the exclusion of the interference from other factors,the minimum purchase price policy for grain had a positive impact on the planting area of rice in Hubei Province.That is,the minimum purchase price policy significantly stimulated the growth of rice planting area in Hubei Province.展开更多
MODIS （Moderate Resolution Imaging Spectroradiometer） is a key instrument aboard the Terra （EOS AM） and Aqua （EOS PM） satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classi...MODIS （Moderate Resolution Imaging Spectroradiometer） is a key instrument aboard the Terra （EOS AM） and Aqua （EOS PM） satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classification of land covers. Shaoxing county of Zhejiang Province in China was chosen to be the study site and early rice was selected as the study crop. The derived proportions of land covers from MODIS pixel using linear spectral mixture models were compared with unsupervised classification derived from TM data acquired on the same day, which implies that MODIS data could be used as satellite data source for rice cultivation area estimation, possibly rice growth monitoring and yield forecasting on the regional scale.展开更多
基金funded through projects of the National Key Research and Development Program of China(2023YFD1301401)Cheng Wei received the grant.Ministry of Science and Technology of the People’s Republic of China(https://www.most.gov.cn/index.html,accessed on 19/03/2024)+1 种基金And the Guizhou Provincial Science and Technology Projects(QKHPTRC-CXTD[2022]1011)Chao Chen received the grant.Guizhou Provincial Department of Science and Technology(https://kjt.guizhou.gov.cn/,accessed on 19/03/2024).
文摘In artificially controlled pot experiments,perennial ryegrass was mixed with other leguminous plants(white clo-ver and alfalfa)and treated with lead,zinc and cadmium(337 mg·kg^(-1),648 mg·kg^(-1),and 9 mg·kg^(-1),respectively)to simulate compound pollution conditions.The results showed that the concentrations of heavy metals,trans-port factors,and bioconcentration factors in mixed planting of ryegrass decreased compared with those in mono-culture.Regardless of whether heavy metal pollution was introduced,mixed planting increased the aboveground and underground biomasses of ryegrass.The different mixed planting treatments had no significant impact on the chlorophyll concentration of ryegrass.The mowing time,mixed planting treatment,and heavy metal treatment had impacts on antioxidant and osmotic adjustment substances,and there were some interactions.The mixed planting treatment did not significantly affect glutathione concentration,cysteine concentration,or nonprotein thiol.Mixed planting generally increased the nitrogen and phosphorus concentrations of ryegrass while reducing the stoichiometric ratio of carbon,nitrogen,and phosphorus.These results suggest that the mixed planting of ryegrass with legumes promotes the growth of ryegrass in the presence of high concentrations of heavy metal pollution.However,it does not enhance the ability of ryegrass to remediate heavy metal pollution in the soil.
文摘African mahogany, one of the world’s most valuable timber species is threatened by over-exploitation in natural forests and failure of plantations due to attacks by the shoot borer Hypsipyla robusta. Mixed-species plantations has been reported to be an effective component of integrated pest management of major pest in other crops;but there is very limited empirical data on its use for managing Hypsipyla in mahogany mixed stands in West Africa. The aim of this study was to assess the effect of mixed-species stands as management intervention, on the growth of Khaya grandifoliola and Khaya ivorensis in relation to Hypsipyla robusta attack in a 10 ha experimental plantation in the wet evergreen forest type in Ghana. Khaya grandifoliola recorded faster growth than Khaya ivorensis in this forest type though the later naturally grow in this forest type while the former is introduced from the dry forest. Two years after planting, diameter and height growth were greater in the mixed-species stand than the pure stands for K. grandifoliola and K. ivorensis. Hypsipyla damage was less in the mixed stands of both K. grandifoliola and K. ivorensis compared to the pure stands, with the 20% and 10% Khaya mixed stand recording the lowest attack in both species. It can be recommended that mixed stands of the two Khaya species at 20% or lower Khaya density might be ideal for reducing the levels of Hypsipyla attack in this type of forest.
文摘Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and mixed plantations of Eucalyptus camaldulensis and Cupressus lusitanica and their impact on the regeneration of woody plants in relation with light. Data on the regenerated woody plants, individual characteristics of the plantation species and light reaching under the canopies were collected using sample plots (n = 4) with a size of 20 m × 20 m for each plantation type. The result showed that, E. camaldulensis was suppressing the growth of C. lusitanica while its growth was favored when it was mixed with C. lusitanica (p < 0.05). There were no significant differences between the pure and mixed plantations in their diversity and density of undergrowth woody plants (p > 0.05). Density of plantation trees were found not having a significant relationship with diversity of species (p = 0.801). There was a significant but not direct relationship between light reached in the understory of the canopies and diversity of species in the plantations (p = 0.027). Overall, the result indicated that both the pure and the mixed plantations were favoring the recruitment of woody plants.
文摘The numerical modeling for the cool water outfall discharge from the LNG Plant is undertaken using CORMIX to evaluate the design of diffuser for discharge. The hydrodynamic data tide and currents are used inputs to the model. It is then calibrated using monitored data. The software has been run to calculate the mixing zone and dilution patterns for various flow conditions. Model result shows that ambient condition is achieved within 64 m from the proposed outfall locations. From the results of the modeling studies it can be concluded that the proposed diffuser design and outfall locations are suitable for all tide conditions. It also shows that there is no significant impact on the marine life due to the proposed cool water discharge, beyond the small area around the discharge location, as the parameters are attaining near ambient water quality within the acceptable space and time.
基金Key R&D Program Major Project of Ningxia(2019BBF02016)New Technology Extension Project of Animal Husbandry in Autonomous Region Feed Workstation.
文摘[Objectives]This study was conducted to investigate the appropriate addition amounts of lactic acid bacteria and cellulase in the mixed silage of potato plants,so as to provide a basis for the rational use of potato plants.[Methods]Fresh potato(Solanum tuberosum)seedling plants,watermelon(Citrullus lanatus)plants,and melon(Cucumis melo)plants were selected as raw materials for silage,each of which was added at a ratio of 32%,and 4%of brown flour was added additionally.On this basis,an L 9(32)orthogonal experiment was designed to investigate the effects of the amount of lactic acid bacteria(10,20,30 g/kg)and the amount of cellulase(5,10,15 g/kg)on the experimental results with sensory evaluation score as an investigation index.[Results]With the increase of the amount of lactic acid bacteria and the amount of cellulase,the sensory evaluation score of silage increased,and it was the highest when the amount of lactic acid bacteria added was 20 g/kg and the amount of cellulose was 10 g/kg.With the increase of the amounts of lactic acid bacteria and cellulase added,ammonia nitrogen showed a decreasing trend,and the pH and ammonia nitrogen were the lowest when the amount of lactic acid bacteria added was 20 g/kg and the amount of cellulose was 10 g/kg.[Conclusions]This study provides a theoretical basis for the rational use of effective ingredients and nutrients in potato plants and the development of new feed resources.
文摘Plants in the alpine zone mainly depend on the reserved food materials stored in their rhizomes for the next growing season. We investigated the effect of mixed cropping （Phaseolus vulgaris L. var. Pinto） with four rhizomatous medicinal plants, i.e., Angelica glauca, Arnebia benthamii, Rheum emodi and Pleurospermum angelicoides as well as three levels of water stress treatment under two conditions （shade net and open field） on macronutrients （NPK） and biochemicals （carbohydrates and protein）. The experiment was conducted by completely randomized design （CDR）. The data were analyzed with ANOVA as well as CDR. The experimental results show that in all the species shade conditions with sever water stress （SSWS） increased the level of macronutrients （NPK）. However, （N） concentration was highest under shade with mixed cropping （SMIX）. Under SMIX, carbohydrate content was highest than open field control conditions （CONT）. This investigation results demon- strate that mixed cropping of medicinal plants with Phaseolus vulgaris could be a good livelihood option in the mountainous regions of Indian Central Himalaya. And the water-stress conditions along with mixed cropping could improve the biochemical constituents in the rhizome of these species.
基金Supported by the Humanities and Social Sciences Foundation for Young Scholars of Ministry of Education of China(11y3jc630197)
文摘Impacts of the minimum purchase price policy for grain on the planting area of rice in Hubei Province were analyzed based on a mixed linear model.After the indicator system containing the minimum purchase price policy and other factors influencing the planting area of rice was constructed,principal component analysis of the system was conducted,and then a mixed linear model where the planting area of rice was as the dependent variable was established.The results show that after the exclusion of the interference from other factors,the minimum purchase price policy for grain had a positive impact on the planting area of rice in Hubei Province.That is,the minimum purchase price policy significantly stimulated the growth of rice planting area in Hubei Province.
文摘MODIS （Moderate Resolution Imaging Spectroradiometer） is a key instrument aboard the Terra （EOS AM） and Aqua （EOS PM） satellites. Linear spectral mixture models are applied to MOIDS data for the sub-pixel classification of land covers. Shaoxing county of Zhejiang Province in China was chosen to be the study site and early rice was selected as the study crop. The derived proportions of land covers from MODIS pixel using linear spectral mixture models were compared with unsupervised classification derived from TM data acquired on the same day, which implies that MODIS data could be used as satellite data source for rice cultivation area estimation, possibly rice growth monitoring and yield forecasting on the regional scale.
