RESUMO
The generic diagnostic characters of Paracercopis (Hemiptera: Cercopoidea: Cercopidae) are redefined and the autapomorphies are proposed to support the monophyly of the genus. Scanning electron micrographs of antennal sensilla and sensilla on rostral apex of P. seminigra (Melichar, 1902) are provided for the first time. A checklist together with new distribution records and key to the species of the genus are provided. Host plant associations of Paracercopis species are reported for the first time. Paracercopis unicolor Liang, Zhang & Xiao, sp. nov., representing the seventh and largest species of the genus is described from Hubei Province in south central China.
Assuntos
Hemípteros , Animais , China , Microscopia , SensilasRESUMO
Wetland plant diversity reveals key aspects of the environmental and ecological status of wetlands and plays an important role in the maintenance of ecosystem functions and services. The present study surveyed the plant species diversity of 22 wetlands in Beijing and, combining field data and remote sensing data, evaluated ecological qualities of the wetlands based on indicators of habitat status, plant species diversity, typical wetland plant community, and status of alien plant invasion. A total of 338 species (including varieties and subspecies) belonging to 220 genera of 74 families of wetland plants were recorded in Beijing. The wetlands could be divided into four types according to plant species composition, which showed a spatial gradient pattern from urban core to ecological conservation areas. Wetlands located in ecological conservation areas were of better ecological quality than those located in urban core and suburban plain areas. The value of ecological quality index (EQI) for Baihe River, Huaishahe-Huaijiuhe River, Jinniu Lake, Hanshiqiao Wetland, and Yongdinghe River (Mentougou Section) were in the top five, whereas the value of EQI for river-type wetlands located in suburban plain areas were relatively lower. The results of the canonical correspondence analysis indicated that the most critical factors affecting wetland plant species composition were the distance to the nearest road, water total nitrogen, and area percentage of ecological green land. Furthermore, the results of the canonical correlation analysis indicated that the most critical factors affecting wetland plant species diversity were the area percentage of construction land and water total organic carbon. Human activity intensity and water quality have a strong impact on the plant diversity and ecological quality of wetlands in Beijing. It is suggested that efforts should be made to strengthen the ecological protection and restoration of the river-type wetlands located in suburban plain areas.
Assuntos
Ecossistema , Áreas Alagadas , Pequim , China , Conservação dos Recursos Naturais/métodos , Humanos , Plantas , RiosRESUMO
The comprehensive evaluation of terrestrial biodiversity is a key basic work for biodiversity protection. Clarifying the status, trend, and driving factors of biodiversity is premise and necessary for formulating policies and measures of biodiversity protection. At present, there is no unified indicator system for the comprehensive assessment of terrestrial biodiversity in China. We constructed a comprehensive assessment indicator system of terrestrial biodiversity in China, by combining the Aichi biodiversity targets of the Convention on Biological Diversity and the sustainable development goals of the United Nations, learning from the development trend of biodiversity assessment in the world, and following the Pressure-State-Response framework. A total of 22 indicators were obtained, including eight status indicators, seven pressure indicators, and seven response indicators. The correlation and accessibility of the indicators were analyzed. These indicators could be applied to not only an independent assessment for biodiversity status, threatened and protection effectiveness, but also for the comprehensive assessment of terrestrial biodiversity to optimize and adjust priority protection areas and protection measures. Our results would provide a technical support for calculating green GDP and formulating regional ecological compensation policies.
Assuntos
Biodiversidade , Conservação dos Recursos Naturais , China , Desenvolvimento SustentávelRESUMO
The beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), is an important pest of numerous crops, and it causes economic damage in China. Use of secondary metabolic compounds in plants is an important method used to control this insect as a part of integrated pest management. In this study the growth, development, and food utilization of three successive generations of S. exigua fed on three cotton gossypol cultivars were examined. Significantly longer larval life-spans were observed in S. exigua fed on high gossypol cultivar M9101 compared with those fed on two low gossypol cultivars, ZMS13 and HZ401. The pupal weight of the first generation was significantly lower than that of the latter two generations fed on ZMS13 group. Significantly lower fecundity was observed in the second and third generations of S. exigua fed on M9101 compared with S. exigua fed on ZMS13 and HZ401. The efficiency of conversion was significantly higher in the first and third generations fed on HZ401 compared with those fed on ZMS13 and M9101. A significantly lower relative growth rate was observed in the three successive generations fed on M9101 compared with those fed on ZMS13 and HZ401. Cotton cultivars significantly affected the growth, development, and food utilization indices of S. exigua, except for frass and approximate digestibility. Development of S. exigua was significantly affected by relative consumption rate and efficiency of conversion of ingested food, but not by relative growth rate or approximate digestibility, suggesting that diet-utilization efficiency was different based on food quality and generation. Measuring the development and food utilization of S. exigua at the individual and population levels over more than one generation provided more meaningful predictions of long-term population dynamics.
Assuntos
Dieta , Gossipol/farmacologia , Controle de Insetos/métodos , Spodoptera/efeitos dos fármacos , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , China , Fertilidade/efeitos dos fármacos , Larva/fisiologia , Dinâmica Populacional , Spodoptera/crescimento & desenvolvimentoRESUMO
A new species of Leptobrachella, Leptobrachella wulingensis sp. nov. is described based on specimens collected from the Wuling mountains in Hunan Province, China. The new species can be distinguished from its congeners by a combination of having a SVL body size range of 24.5-32.8 mm in four adult males and 29.9-38.5 mm in three adult females; dorsal surface brown to reddish brown with indistinct markings; ventral surface creamy white, often with pale brown speckling on chest and margins; flanks with small to moderate black spots; skin on dorsum shagreened with sparse large warts, sometimes with short longitudinal ridges; toes with rudimentary webbing and narrow lateral fringes; dermal ridges under toes interrupted at the articulations; and iris bicolored with a bright orange or golden upper half, fading to silver in the lower half. Uncorrected sequence divergence between L. wulingensis sp. nov. and homologous 16S rRNA sequences available for all known species in the genus are ≥ 2.3%-2.9%.
Assuntos
Anuros , Animais , Tamanho Corporal , China , Feminino , Masculino , RNA Ribossômico 16SRESUMO
To examine the potential of a suite of biomarkers as early warning indicators of environmental pollution, sperm count, neutral red retention time (NRRT) and DNA damage were measured in earthworm Eisenia fetida exposed to increasing concentrations of acetochlor in OECD soil. The neutral red retention time of earthworms coelomocytes was sensitive to acetochlor pollution, and decreased significantly when the concentration was more than 10mgkg(-1) after 30 and 60 days of exposure (P<0.05). The reduced neutral red retention time correlated with the soil acetochlor residual. Sperm count decreased significantly at the concentrations of 40 and 80mgkg(-1) after 15 days of exposure (P<0.05). The DNA damage of earthworms coelomocytes increased significantly after 30 days of exposure at the highest concentration (80mgkg(-1); P<0.05). Earthworms were under physiological stress at field dose of acetochlor (10mgkg(-1)). Higher concentrations of acetochlor caused sperm count decrease and DNA damage of earthworms. Such a suite of biomarkers could serve as indicators of the health of the soil environment and to evaluate the toxicity of acetochlor on earthworms or as a means of monitoring soil acetochlor pollution.
Assuntos
Dano ao DNA/efeitos dos fármacos , Monitoramento Ambiental/métodos , Herbicidas/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Toluidinas/toxicidade , Animais , Biomarcadores/análise , Relação Dose-Resposta a Droga , Exposição Ambiental , Herbicidas/análise , Vermelho Neutro/análise , Vermelho Neutro/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/análise , Contagem de Espermatozoides/veterinária , Fatores de TempoRESUMO
To assess the sublethal toxicity of the herbicide acetochlor to earthworms and to find out biomarkers possible inducted under acetochlor exposure, Eisenia fetida was exposed to artificial soils supplemented with different concentrations of acetochlor(5, 10, 20, 40 and 80 mg/kg soil). Effects of the acetochlor on cytochrome P450 monooxygenases p-nitroanisole O-demethylase (ODM), aldrin epoxidase (AE) and glutathione-S-transferases (GSTs) activities were determined. The results revealed cytochrome P450 monooxygenases were elevated with increasing concentrations of acetochlor, and the AE activity increased significantly compared with control at the concentration of 80 mg/kg (P < 0.05). However, ODM activity from E. fetida was not induced significantly by acetochlor at all treatments (P > 0.05). Sodium dodecyl sulfate-polyacryamide gel electrophoresis (SDS-PAGE) showed that one protein band was visualized and no evident differences were found in protein profiles between treatments and control. The GST activity increased significantly with longer duration(P < 0.05) and increasing concentrations of acetochlor exposure (P < 0.05). This study showed that the monooxygenases and GSTs activities in E. fetida could be induced by acetochlor, and thus, the AE and GST could be used in sublethal assays for soil contamination surveys and GST could be used as biomarkers ofacetochlor exposure in E. fetida.
Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa Transferase/metabolismo , Herbicidas/farmacologia , Oligoquetos/efeitos dos fármacos , Toluidinas/farmacologia , Animais , Cromatografia Gasosa , Eletroforese em Gel de Poliacrilamida , Microssomos/efeitos dos fármacos , Microssomos/enzimologia , Oligoquetos/enzimologiaRESUMO
In this paper, an ecological vulnerability evaluation index system for the Shengli Coalfield in Xilinguole of Inner Mongolia was established, which included 16 factors in ecological sensitivity, natural and social pressure, and ecological recovery capacity, respectively. Based on the expert scoring method and analytic hierarchy process (AHP), an ecological vulnerability model was built for the calculation of the regional ecological vulnerability by means of RS and GIS spatial analysis. An analysis of the relationships between land use and ecological vulnerability was also made, and the results were tested by spatial auto-correlation analysis. Overall, the ecological vulnerability of the study area was at medium-high level. The exploitation of four opencast areas in the Coalfield caused a significant increase of ecological vulnerability. Moreover, due to the effects of mine drained water and human activities, the 300 -2000 m around the opencast areas was turning into higher ecologically fragile area. With further exploitation, the whole Coalfield was evolved into moderate and heavy ecological vulnerability area, and the coal resources mining was a key factor in this process. The cluster analysis showed that the spatial distribution of the ecological vulnerability in the study area had reasonable clustering characteristics. To decrease the population density, control the grazing capacity of grassland, and regulate the ratios of construction land and cultivated land could be the optimal ways for resolving the natural and social pressure, and to increase the investment and improve the vegetation recovery coefficient could be the fundamental measures for decreasing the ecological vulnerability of the study area.
Assuntos
Minas de Carvão , Ecossistema , Modelos Teóricos , China , Sistemas de Informação Geográfica , Tecnologia de Sensoriamento RemotoRESUMO
China is one of the origin centers of rice (Oryza sativa), with a distribution of abundant wild rice germplasm resources. Since the biosafety certificates were issued to Bt transgenic rice containing cry1Ac gene against lepidopteran pests, concerns are raised on the gene flow from transgenic rice to its wild relatives. This paper reviewed the occurrence of transgenic rice gene flow and its potential ecological consequences. Most studies suggested that transgenic rice could successfully hybridize with cultivated rice, wild rice (O. rufipogon), red rice (O. sativa f. spontanea), and barnyard grass (Echinochloa caudata), and the gene flow from transgenic rice had a lower occurrence frequency and was highly variable. Once the gene flow successfully occurred, the transgenes could introgress into a wild population within only a few generations because of the fitness advantage of transgenic rice due to the new selective traits of transgenes. When the transgenic plants invaded and persisted in a wild population, the dynamic changes of the mixed population would depend on the relative fitness and competition capability. To study the effects of the gene flow of transgenic rice and its long-term ecological consequences would have significance in rationally protecting and utilizing wild rice germplasm resources in China.