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开发老区寻找“水区”油气地质储量的途径与方法
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作者 方锡贤 《录井工程》 2023年第3期107-112,共6页
相对于“干带”,开发老区中的“水区”储层物性较好,产液量较高,发现油层投产能够收到较好效益。为了在“水区”中发现油层,在介绍采油区内部查漏补缺、采油区周缘水区扩边、“空白层段”“空白带”“空白圈闭”寻找油层以发现“水区”... 相对于“干带”,开发老区中的“水区”储层物性较好,产液量较高,发现油层投产能够收到较好效益。为了在“水区”中发现油层,在介绍采油区内部查漏补缺、采油区周缘水区扩边、“空白层段”“空白带”“空白圈闭”寻找油层以发现“水区”油气地质储量的基础上,探讨了在采油区内部通过平面分析、纵向对比、完善解释图板、校正构造、细分小层等途径寻找“水区”油层,在采油区周缘“水区”通过分析成藏主控因素、油水界面实现油层扩边,在“空白层段”“空白带”“空白圈闭”通过运用成藏规律分析、微构造分析、圈闭类比分析、加深钻进等发现油层的开发老区“水区”找油的可行技术方法。经试油验证,以上一些解释评价方法应用效果较好,可为在开发老区的“水区”寻找油气地质储量提供线索。 展开更多
关键词 开发老区 “水区” 对比分析 圈闭分析 储量发现
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Analysis on Vapour Field for the Drought Causes in Beijing,Tianjin and Hebei Districts in Recent Years 被引量:4
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作者 杨文霞 李宏宇 +1 位作者 李宗涛 房彬 《Agricultural Science & Technology》 CAS 2010年第1期117-121,共5页
The monthly variation,temporal-spatial distribution,transportation characteristics of vapour field at middle and lower atmosphere and their effects on drought in Beijing,Tianjin and Hebei districts were studied,which ... The monthly variation,temporal-spatial distribution,transportation characteristics of vapour field at middle and lower atmosphere and their effects on drought in Beijing,Tianjin and Hebei districts were studied,which have a guiding significance on predicting climate and arranging agricultural production in the district. 展开更多
关键词 BEIJING Tianjin and Hebei district DROUGHT Vapour field
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Sugarcane Requirement of Water and Effect of Fertigation on Sugarcane 被引量:1
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作者 谭宏伟 周柳强 +1 位作者 谢如林 黄美福 《Agricultural Science & Technology》 CAS 2009年第4期175-177,182,共4页
The sugarcane is a main sugar crop in China. The seasonal drying is one of the problems that influence the improvement of output and quality of sugarcane in China. The experimental results for the water requirement an... The sugarcane is a main sugar crop in China. The seasonal drying is one of the problems that influence the improvement of output and quality of sugarcane in China. The experimental results for the water requirement and fertigation of the sugarcane showed, that the distribution of the rainfall in spring, autumn and winter, all could not suit the requirements for sugarcane growth. Detailedly, it can suit that sugarcane requirement of 74.4%, 68.6% and 35.7% respectively at seedling emerging stage, tillering stage and mature stage according to sugarcane growth. The drought has already limited the yield of sugarcane. Application of fertigation can enhance the fertilizer use efficiency, and it is also a water saving technique in sugarcane production. 展开更多
关键词 Sugarcane planting area Distribution of rainfall Water requirement of sugarcane FERTIGATION
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Impacts of Agricultural Non-point Pollution on Water-source Area in Songhua Dam 被引量:2
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作者 钟萍 段宗亮 《Agricultural Science & Technology》 CAS 2012年第11期2375-2378,共4页
[Objective] The aim was to research impacts of agricultural non-point pol- lution on water-source region in Songhua Dam, laying foundation for control of water pollution and scientific protection of water-source regio... [Objective] The aim was to research impacts of agricultural non-point pol- lution on water-source region in Songhua Dam, laying foundation for control of water pollution and scientific protection of water-source region. [Method] Water in Muyang River, lengshui River and Zizania aquatica region were sampled to measure content of pollutants in water and conclude relation between water contamination and agri- cultural non-point pollution to find the major cause of pollution. [Result] Organic pollu- tant in Muyang River was higher; N and P contents in Lengshui River were higher; the measured indices in Zizania aquatica region excessively exceeded related stan- dard. [Conclusion] The chemical fertilizers and pesticides are the toxic materials lead- ing to water contamination and constitute a major cause of pollution in Songhua Dam water-source region. Agricultural non-point pollution should be controlled in a scientific way. 展开更多
关键词 Songhua Dam Reservoir Water-source region Agricultural non-pointpollution
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Effects of water stress on Haloxylon ammodendron seedlings in the desert region of Heihe inland river watershed, Gansu Province, China 被引量:2
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作者 刘发民 仵彦卿 +1 位作者 苏建平 杜明武 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期197-201,共5页
The water relation and leaf gas exchange of saxoul (Haloxylon Ammodendron Bge, a C4 shrub) seedlings were studied under water stress in 2001. Saxoul seedlings maintained high transpiration when the soil moisture was a... The water relation and leaf gas exchange of saxoul (Haloxylon Ammodendron Bge, a C4 shrub) seedlings were studied under water stress in 2001. Saxoul seedlings maintained high transpiration when the soil moisture was above 11%. The seedlings were able to take up water from soil with above 6 % soil water content, which was the threshold level of soil moisture for seedlings. The relationship between transpiration and potential evaporation was linear for well-watered seedlings. The de-crease of soil water availability led to different degrees of down-regulation of stomatal conductance, leaf transpiration and net CO2 assimilation rate. The stomata played a relatively small part in determining the net CO2 assimilation rate for the same seedling. The relationship between net CO2 assimilation rate and transpiration was linear diurnally, and reduction scale of leaf transpiration was much bigger than that of net CO2 assimilation rate by waters tress treatments, therefore intrinsic wa-ter-use-efficiency increased. High evaporative demand increased the leaf transpiration but inhibited net CO2 assimilation rate. Because of the effect of VPD on transpiration in this region, the transpiration of well-watered and mild water stress seedlings becomes responsive to change in stomatal conductance over a wider range. 展开更多
关键词 Haloxylon ammodendron Water stress Leaf gas exchange Water relation Stomatal conductance SEEDLING
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Pollen Assemblage Features of Modern Water Samples from the Shiyang River Drainage, Arid Region of China 被引量:7
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作者 朱艳 陈发虎 +2 位作者 程波 张家武 David B.MADSEN 《Acta Botanica Sinica》 CSCD 2002年第3期367-372,共6页
Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to c... Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to carry pollen and spores, and to assess the contribution of the water-borne pollen to pollen assemblages in lake sediments at the end of the river system. Results indicate the pollen assemblages in water samples consist of both local and upland pollen. Percentages of upland pollen reach 30% - 60%, and pollen assemblages in water samples do not indicate the nature of local vegetation at the sampling sites. Fluvial currents have the capacity to transport large quantities of pollen long distances, and the contribution of this fluvial transported pollen is relatively high, For example, percentages of Picea Dietr. pollen in water samples at sampling sites 130 km and 145 km away from Picea forests reach 16.5% and 7.7%, respectively. Fluvial pollen transport occurs primarily during flood periods, and pollen concentrations from the flood samples are 17.1 - 12.5 times those from normal fluvial flow. Reservoirs affect pollen transportation since pollen is deposited at reservoir inlets and pollen concentrations are much reduced at reservoir outlets. Human activity can thus change natural features of pollen transportation and deposition. The main factors influencing pollen concentrations and assemblages are sampling time, sampling location, and rainfall intensity. 展开更多
关键词 pollen analysis modern river water Shiyang River arid region of China
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:38
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarded as the northern limit of the subtropical vegetation zone; 2) the northern limit of subtropical vegetation zone in China is along the northern coast of the Yangtze River, from Hangzhou Bay, via Taihu Lake, Xuancheng and Tongling in Anhui Province, through by southern slope of the Dabie Mountains, to Wuhan and its west, coinciding with a warmth index ( WI ) value of 130-140 ℃·month; 3) the tropical region is limited in a very small area in southeastern Hainan Island and southern edge of Taiwan Island; and 4) considering a significant difference in climates between the southern and northern parts of the warm temperate zone, we suggested that the warm temperate zone in China is divided into two vegetation regions, deciduous broadleaf woodland region and deciduous and evergreen broadleaf mixed forest region, the Qinling Mountain_Huaihe River line being as their boundary. We also claimed that the zonal vegetation in North China is deciduous broadleaf woodland. Finally, we emphasized the importance of dynamic vegetation regionalization linked to climate changes. 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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Study on the Occurrence and Epidemic Regularity and Region Division of Rice Blast in Nanchong City 被引量:1
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作者 彭昌家 白体坤 +2 位作者 丁攀 冯礼斌 杨宇衡 《Agricultural Science & Technology》 CAS 2016年第4期927-937,共11页
With the aim to improve the level of monitoring and warning as well as the comprehensive control of rice blast disease, and to feasibly reduce the disease threat in Nanchong City, the methods of GPS and GIS, systemati... With the aim to improve the level of monitoring and warning as well as the comprehensive control of rice blast disease, and to feasibly reduce the disease threat in Nanchong City, the methods of GPS and GIS, systematical monitoring and field survey, rice blast resistance identification, physiologic races of rice blast monitoring, and meteorological data analysis were performed to study the occurrence and epidemic region division, precise demarcation and occurrence and epidemic regularity of rice blast in Nanchong City. This study first completed the epidemic region division and precise demarcation; first clarified the initial affection(beginning period) locations, occurrence characteristics, epidemic trends and characteristics; explicated the existence of four epidemic peak periods of rice blast in the field, where the damage areas of first peak period played a decisive role during the blast epidemic years; in late May, the cumulative occurrence areas and annual occurrence areas presented higher positive correlation with the correlation coefficient of 0.817;and established a prediction model of occurrence areas per year based on the disease field rate at the end of boot stages and the diseased plant rate at dough stages. The results of investigation on the impact factors investigation of blast disease in Nanchong in recent years suggested that the internal causes were the decrease or loss of blast resistance of the rice cultivars, as well as the increase of physiological races with strong resistance to rice blast and the emergence of new virulent physiologic varieties; the external causes were suitable temperature, too much rainy, and sunlight shortage. Between 2010 and 2015, the short-term forecast accuracy for rice blast in Nanchong was up to 100%, and medium-and long-term forecast accuracy was also up to 98% and 95%, respectively, which increased by 5-15% than that before 1997, thereby making the control effect of rice blast in Nanchong increased by 15-30%. 展开更多
关键词 Rice Rice blast Region division Occurrence characteristics Epidemic regularity Early warning level
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Effect of Flooding and Air-drying on Nutrition Content of Soil in Embankment WLFZ of Chaohu Lake 被引量:1
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作者 匡武 吴添天 +2 位作者 张彦辉 严云志 芮明 《Agricultural Science & Technology》 CAS 2015年第8期1751-1756,共6页
Organic matter (OM), total nitrogen (TN), organic phosphorous (OP) and total phosphorous (TP)content of soil in northwest water-level fluctuating zone (WLFZ) of Lake Chaohu under natural and different artifi... Organic matter (OM), total nitrogen (TN), organic phosphorous (OP) and total phosphorous (TP)content of soil in northwest water-level fluctuating zone (WLFZ) of Lake Chaohu under natural and different artificial conditions were ana- lyzed to study the variation of OM, TN, OP and TP. It showed: Flooding and air- drying help to increase soil OM content in study area. Process of flooding and air- drying is conducive to soil adsorption of nitrogen and it can enhance spatial hetero- geneity of soil OM, TN, OP, process of flooding and air-drying also can reduce the difference of TP contents among different points. Riprap embankment is not con- ducive to maintaining soil organic matter under flooded conditions, emergent plants are conducive to maintaining soil organic matter under flooded conditions. Soil with high nitrogen content will release nitrogen to overlying water under flooded condi- tions. Under drying after flooding conditions, demand for phosphorus of vegetation growth will reduce TP content in soil, bare area will enrich phosphorus, when the next flood cover up a greater release of phosphorus will happen 展开更多
关键词 Flooding and air-drying WLFZ Organic matter NITROGEN Phosphorous
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Temporal and Spatial Variation Characteristics of Precipitation during Crop Growing Season in Northeast China 被引量:1
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作者 李秀芬 李帅 +2 位作者 纪瑞鹏 郭春明 姜丽霞 《Agricultural Science & Technology》 CAS 2010年第6期137-140,168,共5页
[Objective] The aims were to understand variation characteristics of water resources and provide theoretical guidance for the formulation of agricultural irrigation methods.[Method] Taking the precipitation records du... [Objective] The aims were to understand variation characteristics of water resources and provide theoretical guidance for the formulation of agricultural irrigation methods.[Method] Taking the precipitation records during crop growing season(from April to September)observed by 177 weather stations from 1971 to 2008 in the three provinces of Northeast China(Heilongjiang,Jilin and Liaoning)as research data,annual change and spatial distribution characteristics of precipitation during crop growing season were analyzed by means of small grid interpolation and climatic trend rate.[Result] The precipitation during crop growing season general exhibited the decreasing trend and the precipitation trend rate was-8.6 mm/10a in Northeast China.In addition,there was lack of rain from 1971 to 1980 and relatively abundant of rain during 1981 and 1990 respectively.Moreover,the precipitation obviously exhibited decreasing trend from 1991 to 2008.But the decreasing trend was inconsistent in spatial distributions,that was,the precipitation slightly increased in relatively rainless areas and obviously decreased in relatively rainy areas.[Conclusion] The areas with obvious decreasing trend of precipitation during crop growing season are the main grain producing zones in Northeast China,so the problem of food production security caused by the precipitation changes should be paid enough attention. 展开更多
关键词 Regions in the Northeast China Precipitation during crop growing season Temporal and spatial Variations
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Effects of Fertilization on Moisture Content of Soils in the Loess Hilly-gully Region 被引量:1
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作者 徐宣斌 高照良 《Agricultural Science & Technology》 CAS 2015年第2期278-280,共3页
[Objective] The aim of this study was to study the influence of plants on the soil moisture content under different fertilization.[Method] Using sainfoin,sweet clover,Astragalus adsurgens,alfalfa,ryegrass,little flowe... [Objective] The aim of this study was to study the influence of plants on the soil moisture content under different fertilization.[Method] Using sainfoin,sweet clover,Astragalus adsurgens,alfalfa,ryegrass,little flower,white clover as experimental material,this study explored the effects of soil moisture on the improvement of soil quality.[Result] Results showed that the soil moisture content of different plants follows as:sainfoin 〉sweet clover 〉Astragalus adsurgens 〉alfalfa perennial ryegrass 〉small crown 〉white clover,and the average moisture content reached 24.13% which was 2.45% higher than that of control group.At planting white clover,sweet clover,under the condition of 7 kinds of crops,in the treatments without fertilizer and with organic fertilizer,soil moisture content of soil in 0-20 cm grew significantly.[Conclusion] The application of organic fertilizer and growing of plants would improve soil moisture in abandoned fields,enhance the ability of soil water supply,and improve soil fertility. 展开更多
关键词 Plant FERTILIZER Moisture content of soil Loess hilly-gully region
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Analysis on Status and Development Trend of Wind Erosion in Black Earth Region of Northeast China 被引量:2
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作者 刘铁军 珊丹 +2 位作者 郭建英 高天明 赵显波 《Agricultural Science & Technology》 CAS 2011年第12期1925-1928,共4页
In this paper,areas and main factors of wind erosion in black earth region of Northeast China were systematically analyzed,as well as the development trend of wind erosion in black earth region of Northeast China.In a... In this paper,areas and main factors of wind erosion in black earth region of Northeast China were systematically analyzed,as well as the development trend of wind erosion in black earth region of Northeast China.In addition,development trend of wind erosion in black earth region of Northeast China was analyzed from the aspects of the geographic position,climatic change law in recent 40 years and effects of northeast sand land desertification on wind erosion in black earth region,which had provided references for the research and prevention of wind erosion in soil of black earth region of Northeast China. 展开更多
关键词 Black earth region of Northeast China Wind erosion Water loss and soil erosion Wind erosion factors
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Testing and analysis of rainwater quality in Shenyang 被引量:1
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作者 张立成 兰宇 +1 位作者 程亚楠 党维 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期246-250,共5页
To explore the influence of rainwater quality on rain utilization projects the rainwater of building roofs community runoff and municipal outlets which were taken from Hunnan New District of Shenyang was detected and ... To explore the influence of rainwater quality on rain utilization projects the rainwater of building roofs community runoff and municipal outlets which were taken from Hunnan New District of Shenyang was detected and analyzed for one year. The results show that the main pollutants affecting the quality of the rainwater are chemical oxygen demand COD and suspended solids SS which is especially obvious at the beginning of rainfall. With the duration of the rainfall water quality improves.The contents of COD and SS in municipal outlets are the highest which are 167 to 249 mg/L and 119 to 332 mg/L respectively. The contents of COD and SS are 27 to 85 and 106 to 269 mg/L in community runoff 15 to 80 and 50 to 153 mg/L in the rainwater of building roofs.NH4+-N concentrations of the three sampling sites are 1.7 to 5.2 3.7 to 18.2 and 5.2 to 25.6 mg/L. 展开更多
关键词 rainwater quality building roof communityrunoff municipal outlet
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Nitrate Nitrogen Content Characteristics in Groundwater of Typical Planting Areas in Liao River Basin
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作者 牛世伟 宫亮 +4 位作者 蔡广兴 何志刚 陈玥 刘子琪 隋世江 《Agricultural Science & Technology》 CAS 2016年第1期204-208,共5页
The contents of nitrate nitrogen(NO-3-N) in underground water from typical planting areas in Liao river basin were analyzed, so as to provide theoretical basis for rational fertilization and effectively prevent the ... The contents of nitrate nitrogen(NO-3-N) in underground water from typical planting areas in Liao river basin were analyzed, so as to provide theoretical basis for rational fertilization and effectively prevent the NO-3-N content from exceeding standard. The results showed that difference of the contents of NO-3-N in groundwater from different typical planting areas was significant. The highest content of NO-3-N in underground water was 37.4 mg/L from flower-growing region, then 22. 3 mg/L from maize-growing region, 21.9 mg/L from vegetable-growing region, and the lowest content of NO-3-N in underground water was 19.2 mg/L from rice-growing region. Except rice-growing region, the contents of NO-3-N in underground water of the samples in all planting areas were exceeding standard limit; potential health risk still existed in rice-growing region. Accordingly 12.5%-87.5%, 9.4%-75.5%, 17.9%-58.9% and 21.4%-96.0% of the samples were exceeding standard limit in maize growing region, rice-growing region, vegetable-growing region and flower-growing region. The contents of NO-3-N in under-groundwater before the rainy season was higher than that of NO-3-N in under-groundwater after the rainy season at the same depth of the well. 展开更多
关键词 Liao river basin Planting area Underground water Nitrate nitrogen
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Relation between Economic Development Level and Resource and Environment Carrying Capacity of Central Area of Yunnan Province Based on Decoupling Analysis 被引量:4
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作者 程超 童绍玉 +2 位作者 彭海英 闫少凯 刘玲 《Agricultural Science & Technology》 CAS 2015年第12期2829-2832,共4页
Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling ... Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod. 展开更多
关键词 The central area of Yunnan Province Economic development level Re- source and environment carrying capacity Decoupling analysis Scissors difference
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Study on the Characteristics of Ecological Water Requirement in Maijishan Scenic Spot
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作者 蒲金涌 李晓薇 《Agricultural Science & Technology》 CAS 2012年第9期1971-1976,1996,共7页
[Objective] This study aimed to explore the characteristics of ecological water requirement in Maijishan Scenic Spot. [Methed] The characteristics of ecologi- cal water requirement in Maijishan Scenic Spot were analyz... [Objective] This study aimed to explore the characteristics of ecological water requirement in Maijishan Scenic Spot. [Methed] The characteristics of ecologi- cal water requirement in Maijishan Scenic Spot were analyzed based on,the data of soil humidity and meteorology of the spot. [Result] The result showed that the actual annual ecological water requirement in the spot was 678×10^6 m^3, and the proportion of soil water and evapotranspiration were 21% and 79%, respectively; the minimum annual ecological water requirement quota in the spot was 480.27×10^6 m^3, and the proportion of soil water and evapotranspiration were 16% and 84%, respectively; the minimum annual suitable ecological water requirement quota in the spot was 624.22×10^6 m^3, and the proportion of soil water and evapotranspiration were 18% and 82%, respectively. The precipitation was 614×10^6 m^3, and consumptive water surplus reached up to 78×10^6 m^3. The years when the precipitation was higher than the evapotranspiration accounted for 76%. Since 1980s, the evapotranspiration showed a linearly increasing trend. The precipitation was higher than the evapotranspiration from Jun. to Oct. and less than the evapotranspiration from Nov. to Dec. and Jan. to May. Evapotranspiration water requirement was regulated by soil water. The dis- parity between precipitation and evapotranspiration was huge in spring, thus having certain influence on waterfalls and streams in the spot. [Conclusion] The results of this study provided a basis for the rational use and long-term planning of the water sources in Maijishan Scenic Spot. 展开更多
关键词 Maijishan Scenic Spot Ecological Water Requirement CHARACTERISTICS
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Characteristics of Soil Porosity and Changes of Soil Water Content in Eucalyptus Plantation 被引量:1
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作者 熊柳梅 黄金生 +7 位作者 曾艳 黄雁飞 陈桂芬 刘永贤 周柳强 谭宏伟 黄美福 黄玉溢 《Agricultural Science & Technology》 CAS 2015年第4期662-667,共6页
Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for ... Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for soiI water utiIization in eucalyptus pIanting in the red soiI hiI y region of South China. [Method] In the same cIimatic region, soiI sampIes were coI ected from surface soiI Iayer (A), iI uvial horizon (B) and parent material horizon (C) in the upper sIope, middIe sIope and Iower sIope of eucalyptus pIantation, native forest and pine forest, respectiveIy, to determine the soiI porosity and soiI water content and analyze changes and various infIuencing factors of soiI water content in horizontal and vertical direction. [Result] Average soiI porosity in eucalyptus pIantation, native forest and pine forest was 45.9%, 41.4%and 55.3%, respectiveIy; soiI water content in these three forest stands was 13.3%, 13.4% and 15.5%, respectiveIy. In addition, soiI water content in these three forest stands exhibited no significant differences (P&gt;0.05) among different soiI profiIes and sIope positions, but soiI water content in surface soiI Iayer varied significantIy (P&lt;0.05) among different forest stands; in the horizontal direction, soiI water content exerted an extremeIy significant positive correIation with total coverage. [Conclusion] Total coverage of canopy Iayer, herb and Iitter Iayer is one of the most critical fac-tors affecting the changes of soiI water content in surface soiI Iayer of forest stands. 展开更多
关键词 Eucalyptus plantatlon Soil porosity Changes of soil water content Red soli Hilly reglon South China
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The runoff characteristics and harmonic analysis of the soil moisture dynamics in Robinia pseudoacacia stand 被引量:1
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作者 高鹏 刘作新 陈伏生 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期295-298,共4页
Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the wes... Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion. 展开更多
关键词 Hilly semi-arid area Robinia pseudoacacia stand Runoff generation characteristics Soil moisture dynamics Harmonic analysis
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Study on the Floating Plant Climatic Adaptation of Undercurrent Constructed Wetland in North China 被引量:3
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作者 赵振国 刘丽 《Agricultural Science & Technology》 CAS 2011年第9期1331-1333,共3页
[Objective] The aim was to choose appropriate floating plant in the wetland in the north China.[Method] Pistia stratiotes L.,Eichhornia crassipes,and Hydrocharis dubia(Bl.) Backer were planted in the aquatic biologi... [Objective] The aim was to choose appropriate floating plant in the wetland in the north China.[Method] Pistia stratiotes L.,Eichhornia crassipes,and Hydrocharis dubia(Bl.) Backer were planted in the aquatic biological pool of constructed subsurface flow wetland system in the reservoir.Through filed investigation,the growth of the three kinds of plants was studied and their adaptability to the northern climate was concluded.[Result] Judging from the growth speed and state of the three kinds of floating plants,the biological characteristic of Pistia stratiotes L.can perfectly adapt the environment in the pool in the reservoir,followed by the Eichhornia crassipes.The growth state of the Hydrocharis dubia(Bl.) Backer was the worst one and it can not adapt to the north environment.[Conclusion] It provided references for the choice of artificial floating plant in the north area. 展开更多
关键词 North China Undercurrent constructed wetland Duckwood Climatic adaptation
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Soil Moisture Characteristics in Karst Area with Different Land Use Types 被引量:1
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作者 谢世友 任伟 《Agricultural Science & Technology》 CAS 2013年第12期1856-1860,1864,共6页
Ecological efficiency changes of soil moisture were researched in karst areas with different land type uses, including farmland, abandoned farmland (1 y) and shrub land (1 y), sparse wood land (15 y), secondary ... Ecological efficiency changes of soil moisture were researched in karst areas with different land type uses, including farmland, abandoned farmland (1 y) and shrub land (1 y), sparse wood land (15 y), secondary forest (25 y) and the re- sults showed that physical property of soil was not a simple "improvement" process during land type evolution. Specifically, from farmland to secondary forest, the con- tent of topsoils changed from being washed away to accumulation and soil bulk density changed from increasing to decreasing. For example, soil bulk densities of abandoned farmland and shrub land increased by 6.6% and 11.57% compared with farmland, and of sparse wood land and forest land decreased by 5.0% and 10.0%. The change trend of soil bulk density was just in contrary to total porosity. Available water capacity was the lowest of shrub land, but increased in rest land types. The increase tended to be volatile in 5.1%-12.5% of different land types and water-sta- ble aggregate content (〉0.25 mm) reached the highest of sparse wood land. The destruction rate, however, was declining in the process of land type evolution and the increase was in the range of 34.0%-64.7% compared with farmland. The de- struction rate of aggregate was of negative correlation with organic matter. Water- holding capacity was the best of forest land and abandoned farmland and the poor- est of shrub land, close to sparse wood land. Water-supplying capacity from high to low was as follows: farmland〉sparse wood land〉secondary forest〉shrub land〉a- bandoned farmland. It is obvious that water-holding capacity and water-supplying capacity are not consistent, but both are closely related to the content of soil clays, porosity, and aggregate stability. 展开更多
关键词 Karst area Land use type Soil moisture characteristics
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