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Pedosphere and Its Effect on global changes

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Pedosphere 2000年第2期10卷 97-106页

作者： ZHAO QIGUO and CAO HUI(Institute of Soil Science, the Chinese Academy of Sciences, P.O. Box 821, Nauling 210008 China) 中科院南京土壤所江苏南京 210008

With development of modern geoscience, particularly development of environmental sciences, the contemporary soil science is undergoing great changes in both research contents and scope. Soil is not onlya certain substance or a certain independent natural historical body but also a spheric layer with peculiarstructure and functions in the earth system. From the viewpoint of the geo-biosphere system of earth, soilscience does deal not only with the soil substances per se but also more importantly with the relationshipsamong soil, the other spheres and the human survival environment in view of the "pedosphere". This is thenew orientation of soil science today and will affect profoundly the studies on the human survival environmentand global changes. To throw more light on this subject, the present paper intends to address the conceptionof pedosphere and its role in global changes. Also addressed are series of environmental issues in China andtheir relations to the global changes. Moreover, research orientation and priorities are indicated, includingexploitation and protection of the soil resources, soil fertility and sustainable agricultural development, construction of the ecological environment, and the material cycling in pedosphere and its relation to globalchanges.

关键词： earth ecological environment global changes pedosphere soil science

Diversity of symbiotic algae of the genus Symbiodinium in scleractinian corals of the Xisha Islands in the South China Sea

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Journal of Systematics and Evolution 2009年第4期47卷 321-326页

作者： ~(1,2)Zhi-Jun DONG ~1Hui HUANG~* ~1Liang-Min HUANG ~3yuan-Chao LI 1(Key Laboratory of Marine Bio-resourses Sustainable Utilization,South China Sea Institute of Oceanology,Chinese Academy of Sciences, Guangzhou 510301,China) 2(Yantai Institute of Coastal Zone Research for Sustainable Development,Chinese Academy of Sciences,Yantai 264003,China) 3(Hainan Marine Development and Design Institute,Haikou 570125,China) (Key Laboratory of Marine Bio-resourses Sustainable Utilization South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China) (Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China) (Hainan Marine Development and Design Institute Haikou 570125 China)

Symbiotic algae(Symbiodinium sp.)in scleractinian corals are important in understanding how coral reefs will respond to global climate *** present paper reports on the diversity of Syrnbiodinium sp. in 48 scleractinian coral species from 25 genera and 10 families sampled from the Xisha Islands in the South China Sea,which were identified with the use of restriction fragment length polymorphism(RFLP)of the nuclear ribosomal DNA large subunit gene(rDNA).The results showed that:(i)Symbiodinium Clade C was the dominant zooxanthellae in scleractinian corals in the Xisha Islands;(ii)Symbiodinium Clade D was found in the corals Montipora aequituberculata,Galaxea fascicularis,and Plerogyra sinuosa;and(iii)both Symbiodinium Clades C and D were found simultaneously in Montipora digitata,Psammocora contigua,and Galaxea fascicularis.A poor capacity for symbiosis polymorphism,as uncovered by RFLP,in the Xisha Islands indicates that the scleractinian corals have low adaptability to environmental *** studies are needed to investigate zooxanthellae diversity using other molecular markers.

关键词： global changes restriction fragment length polymorphism(RFLP) scleractinian coral South China Sea symbiotic algae(Symbiodinium sp.) Xisha Islands.

Neutral responses of plant community Ca concentration to nitrogen enrichment in a semiarid grassland

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Journal of Plant Ecology 2022年第2期15卷 286-293页

作者： Shuang-Li Hou Xiao-Tao Lü Jun-Jie Yang Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Calcium(Ca)is an essential nutrient for plant growth and Ca concentrations in forage have important implications for ruminant diet and *** remains an open question whether forage Ca concentration would be decreased by increasing nitrogen(N)*** manipulated the increasing rates of N addition(2008–2015)in a semiarid grassland,northern *** Ca concentrations for all species were examined in each plot under N *** Ca concentrations at functional group and community levels were calculated based on the concentration of each species presented and their relative biomass in each *** found that community-level Ca concentration remained stable across a gradient of wide-ranged N addition rates,although Ca concentration at both species and functional group levels showed negative responses to N *** that forbs had higher Ca concentration than grasses,the increasing relative biomass of forbs canceled out the negative responses of species-level and functional group-level Ca *** results further showed that community Ca pool showed a positive but saturating response to N addition,with a threshold at the rate of 10 g N m^(−2)yr^(−1).Our findings highlight the role of changes in plant relative biomass in controlling the responses of forage Ca concentration and stock to N enrichment.

关键词： calcium stock community composition ecological processes global changes nitrogen deposition temperate steppe

Asian Hydroclimate changes and Mechanisms in the Preboreal from an Annually-laminated Stalagmite, Daoguan Cave, Southern China

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 367-377页

作者： LIU Shushuang LIU Dianbing WANG Yongjin ZHAO Kan College of Geography Science Nanjing Normal University

One-year-resolved and annually-counted stalagmite multi-proxies （j180, ~13C, and layer width） from Daoguan Cave, Guizhou Province revealed detailed variability regarding the Asian Summer Monsoon （ASM） and local humidity across Bond events （BE） in the PreboreaL During BEs 8 and 7, 1.5%o enrichments in jlSo values were generally consistent with high- to low-latitude climate changes. In detail, the decadal-scale minor j180 oscillations in BE8 were broadly less than the mean value, in contrast to the significant changes in local soil moisture derived from the j13C values and layer records. In the mid-BE7, jlSo variability was generally above the average level, and higher- amplitude variations were observed in the three proxy indicators. Wavelet analysis on the total jlSo time series and across the specific time windows of BEs 8 and 7 identified periodicities of about 130, 60, and 20-a, respectively. Exceptionally strong in BE7, the 60-a cycle, pervasively observed in instrumental studies, became prominent starting at 11.4 kaBP. Thus, glacial background conditions are important for suppressing the ASM intensity in BE8, while during BE7, tropical hydrological circulations were potentially actively involved. Consequently, climate internal oscillations, analogous to modern conditions, might have occurred in the distant past once the link between the tropical ocean and atmosphere was established as occurs today.

关键词： Daoguan Cave the Preboreal Bond Event ASM global changes

Shrinking greenery： Land use and land cover changes in Kurram Agency, Kohi Safid Mountains of north-western Pakistan

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Journal of Mountain Science 2018年第2期15卷 296-306页

作者： Kamal HUSSAIN Fazlul HAQ Fazlur RAHMAN Department of Geography University of Peshawar Peshawar 25000 Pakistan Department of Geography Government College University Faisalabad Faisalabad 38000 Pakistan

Deforestation and other Land Use and Land Cover(LULC) changes, driven by variety of physical and anthropogenic factors, have altered the mountainous environment. Mountains around the world including northern and north western belts of Pakistan are highly sensitive to deforestation and other LULC changes, which have profound impacts on various sectors of bio-physical and socio-economic systems. Assessment of LULC changes has high significance for protection, conservation and monitoring mountainous environment. The present study is an attempt to assess the landscape changes with particular reference to forest cover depletion in Kurram Agency located in the north western mountain belt of Pakistan. For detailed comparative analysis the study area has been divided into three sections, which coincide with the present administrative divisions of the Agency, i.e., Upper,Lower and Central Kurram. Temporal span of this study covers four decades. In this study, land use map of 1970 and land sat satellite imageries of 1987, 2000 and 2014 were used as spatial data sets. The images were processed and classified into six LULC classes through geospatial packages and change detection maps were prepared for each division and time *** of the study reveal two trends in the four major LULC categories. Forest and rangeland have shrunk, on average, by 15% and 7.5% respectively while, bare soil and rocks outcrops have expanded by 89% and agriculture land by 7.2% in Kurram *** water bodies and snow cover have minor fluctuation in its land area. Major causes of shrinking greenery is attributed to high influx of Afghan refugees and high energy demand of growing population. However, with outflow of the refugees from Kurram agency the general trend in forest cover has reverted and deforestation rate has slowed down.

关键词： Pakistan Tribal areas Deforestation Land Use Land Cover Change Resource management global changes

Climatic and Physiographic Variables to Evaluate Culex pipiens s.l. Risk and Habitat

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Journal of Geoscience and Environment Protection 2022年第8期10卷 1-8页

作者： Maria da Conceição Proença Maria João Alves Maria Teresa Rebelo MARE—Marine and Environmental Sciences Centre & ARNET Aquatic Research Infrastructure Network Associated Laboratory Faculty of Sciences University of Lisbon Lisbon Portugal Department of Physics Faculty of Sciences University of Lisbon Lisbon Portugal National Health Institute Doutor Ricardo Jorge (INSA) &#193 guas de Moura Portugal CESAM-Ciências—Centre for Environmental and Marine Studies Faculty of Sciences University of Lisbon Lisbon Portugal Department of Animal Biology Faculty of Sciences University of Lisbon Lisbon Portugal

Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens s.l. collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters are evaluated. This work is one of the results of a long-term surveillance program of pernicious insects that act as vectors of various diseases;its focus is on the possibility of prevention that can be achieved with abundance data. The focus on Culex pipiens is justified by its abundance and its competence as a vector for numerous health issues. The cumulative distribution of monthly captures by each meteorological parameter allows to compute thresholds corresponding to mosquito massive presence related to 90% of the captures. Using the weather parameters measured in the network of weather stations across the country, a monthly average of each parameter of interest (temperature, humidity, etc.) is computed and an interpolation of the results is made to produce raster maps corresponding to each month. The previously obtained thresholds are applied to each map, producing spatial masks with the relevant zones for each parameter. The intersection of the various masks for each month shows the most densely populated area of Culex, and the ensemble allows us to observe the evolution of mosquito presence through the critical season, which is from May to October at these latitudes. In parallel, mosquito abundance data are related to physiographic parameters. The relative distribution of female mosquitoes across land cover types in each month allows identifying which classes and seasons are most relevant. Orthometric altitude related to the presence of 90% of the catches shows the limits reached by mosquitoes in each month. The results are applied to the previously obtained climate envelopes, delimiting critical areas where the level of risk of transmission of the pathogens for which Culex pipiens is a competent vector is high and countermeasures should b

关键词： Vector-Borne Diseases Transmission Risk Culex pipiens s.l. GIS global changes

Semantic Segmentation of the Intertidal Zone of an Estuary—In Search of the Best Solution

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Journal of Geoscience and Environment Protection 2024年第7期12卷 1-13页

作者： Maria da Conceição Proença Ricardo Nogueira Mendes Ricardo Melo Marine and Environmental Sciences Centre (MARE-ULisboa) & ArNet Lisbon Portugal Department of Physics Faculty of Sciences University of Lisbon Lisbon Portugal Department of Animal Biology Faculty of Sciences University of Lisbon Lisbon Portugal Department of Plant Biology Faculty of Sciences University of Lisbon Lisbon Portugal

An aerial photographic coverage acquired on two consecutive days in October 2021 with a ground resolution of 20 cm and a spectral resolution of 4 bands (red, green, blue and near infrared), allowed to distinguish most of the classes of interest present in the intertidal zone of the Sado estuary. We explored the possibilities of thematic classification in the powerful and complex software ArcGIS Pro;we presented the methodology used in a detailed way that allows others with minimal knowledge of GIS to reproduce the classification process without having to decipher the specifics of the software. The classification implemented used ground truth from four classes related to the macro-occupations of the area. In a first phase we explore the standard algorithms with object-based capabilities, like K-Nearest Neighbor, Random Trees Forest and Support Vector Machine, and in a second phase we proceed to test three deep learning classifiers that provide semantic segmentation: a U-Net configuration, a Pyramid Scene Parsing Network and DeepLabV3. The resulting classifications were quantitatively evaluated with a set of 500 control points in a test area of 37,500 × 12,500 pixels, using confusion matrices and resorting to Cohen’s kappa statistic and the concept of global accuracy, achieving a Kappa in the range [0.72, 0.81] and a global accuracy between 88.9% and 92.9%;the option U-Net had the most interesting results. This work establishes a methodology to provide a baseline for assessing future changes in the distribution of Sado estuarine habitats, which can be replicated in other wetland ecosystems for conservation and management purposes.

关键词： Estuary Intertidal Zone ArcGIS Pro Segmentation global changes

Advances in Grassland Ecosystem Research in Northern Tibetan Plateau

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Agricultural Science & Technology 2009年第3期10卷 148-152页

作者：武建双沈振西张宪洲中国科学院地理科学与资源研究所北京100101 中国科学院研究生院北京100039

With the aggravation of global change, the response and adaptation of the unique ecosystem in Qinghai-Tibet Plateau to global change have been increasingly concerned by scientific community day by day, which makes the sensitivity and fragility of this ecosystem in response to global change widely recognized by scholars. On the basis of introducing the present research process on the degenerate mechanisim, measures of and approaches to recovery, carbon cycle and primary productivity toward global change, we put forward several propositions on studying the alpine grassland ecosystem in Northern Tibetan Plateau.

关键词： Northern Tibetan Plateau Grassland degeneration global changes Carbon cycle Primary productivity