With Longzhou County as example, the weed species, distributions, domi- nant populations and diversity indexes in corn, sugarcane, pineapple, banana and mango fields under different land use patterns in southwest Guan...With Longzhou County as example, the weed species, distributions, domi- nant populations and diversity indexes in corn, sugarcane, pineapple, banana and mango fields under different land use patterns in southwest Guangxi were investi- gated. The results showed that there were 27 families 54 species of weeds in sampling area. Eleven species were Gramineae and ten species were Compositae. There were eight families 13 species in corn fields, ten families 20 species in sug- arcane fields, 12 families 18 species in pineapple fields, ten families 11 species in banana fields and nine families 14 species in mango fields. Bidens bipinnata, Eupa- torium odoratum and Emilia sonchifolia of Compositae were generally occurred with serious harm. Roegneria kamoji, Stellaria media and Bothriochloa intermedia of Gramineae were widely occurred. Weed community made up of Compositae + Gramineae + Oxalidaceae was the main form of dryland weed. The Pielou uniformi- ty of the five use patterns in the studying area were 0.967, 0.964, 0,947, 0.969 and 0.962, respectively, which were high.展开更多
After 30 years of opening-up and reform, the jasmine tea industry in Guangxi has developed into a national pillar industry with special resources in Chi- na. This industry has been influenced by "lnternet+" at vari...After 30 years of opening-up and reform, the jasmine tea industry in Guangxi has developed into a national pillar industry with special resources in Chi- na. This industry has been influenced by "lnternet+" at various aspects. Restricted by the location, information system, brand marketing, the industry should be inte- grated with the "lnternet +" thinking for overall upgrading.展开更多
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore wat...Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.展开更多
基金Supported by Public Welfare Fund Project of Guangxi(GXNYRKS201506)~~
文摘With Longzhou County as example, the weed species, distributions, domi- nant populations and diversity indexes in corn, sugarcane, pineapple, banana and mango fields under different land use patterns in southwest Guangxi were investi- gated. The results showed that there were 27 families 54 species of weeds in sampling area. Eleven species were Gramineae and ten species were Compositae. There were eight families 13 species in corn fields, ten families 20 species in sug- arcane fields, 12 families 18 species in pineapple fields, ten families 11 species in banana fields and nine families 14 species in mango fields. Bidens bipinnata, Eupa- torium odoratum and Emilia sonchifolia of Compositae were generally occurred with serious harm. Roegneria kamoji, Stellaria media and Bothriochloa intermedia of Gramineae were widely occurred. Weed community made up of Compositae + Gramineae + Oxalidaceae was the main form of dryland weed. The Pielou uniformi- ty of the five use patterns in the studying area were 0.967, 0.964, 0,947, 0.969 and 0.962, respectively, which were high.
文摘After 30 years of opening-up and reform, the jasmine tea industry in Guangxi has developed into a national pillar industry with special resources in Chi- na. This industry has been influenced by "lnternet+" at various aspects. Restricted by the location, information system, brand marketing, the industry should be inte- grated with the "lnternet +" thinking for overall upgrading.
基金Supported by the Natural Science Foundation of Guangxi Province,China(Nos.2012GXNSFEA053001,2010GXNSFE013001,2011GXNSFE018002,2011GXNSFA018108)
文摘Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.