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41.
Performance of rainy season greengram as influenced by land configuration and phosphorus application
B. G. Shivakumar B. N. Mishra H. M. Thippeswamy S. S. Balloli 《Archives of Agronomy and Soil Science》2013,59(3-4):371-379
A field experiment was carried out for 2 crop years (July‐October) at the Indian Agricultural Research Institute, New Delhi to study the effect of land configuration and phosphorus levels on the growth and yield of rainy season greengram under limited irrigation facility. The crop sown on 2 meter wide broad bed and furrow (BBF) showed higher growth attributes, nodulation, yield attributes and yield compared to flat bed (FB) sowing. Application of 30 and 60 kg P2O5ha‐1 showed significant increase in growth attributes, nodulation, yield attributes and yield as compared to no phosphorus application. The moisture status in the soil determined the optimum dose of phosphorus needed for greengram. The combination of BBF sowing and application of 60 kg P2O5 ha?1 recorded the highest grain yield among all the combinations of land configuration and phosphorus levels. 相似文献
42.
分析了国家土地督察制度实施5年来存在的主要问题,主要是:土地督察制度建设的法制化不足;土地督察业务建设不规范;工作机制不完善;土地督察队伍仍需加强。针对这些问题,提出了推进土地督察制度建设的建议:加强土地督察制度的法制化和制度化建设;完善土地督察核心业务建设;完善土地督察工作机制;加强土地督察队伍建设。 相似文献
43.
在城市建设中,土地的收购、储备、出让行为,对城市建设和发展的影响非常直接,极其关键。因此,要规范土地收储管理,优化土地资源配置。 相似文献
44.
阿勒泰地区位于北纬44°59′-49°11′和东经85°32′-91°01′,区内分布有高山、丘陵、河谷、平原、沙漠、戈壁和湖泊,土地面积为17750万亩。对该区土地类型进行研究,有助于认识影响土地分异的因素和探讨农业自然分区,为合理利用土地资源,发展农、林、牧业生产提供科学依据。 相似文献
45.
鄂尔多斯西部地区土地荒漠化(退化)及其防治研究──以公卡汗苏木为例 总被引:2,自引:0,他引:2
陈隆亨 《干旱区资源与环境》1994,8(1):62-71
本文分析了鄂尔多斯西部地区荒漠化的现状及发展过程,划分了轻度、中度、重度和严重荒漠化阶段,并分出极易、较易、较难三种潜在荒漠化等级,分别测算了面积,做出了图表。说明了风蚀与水蚀过程的特征。阐述了自然因素与人为因素在土地荒漠化过程中的交互作用。提出了退耕还牧封沙育草、实行防风蚀耕作、发展灌溉农业、合理轮牧、保护植被等防治荒漠化的有效措施。 相似文献
46.
Recent research shows that land use history is an important determinant of current ecosystem function. In the United States,
characterization of land use change following European settlement requires reconstruction of the original property mosaic.
However, this task is difficult in unsystematically surveyed areas east of the Appalachian Mountains. The Gwynns Falls watershed
(Baltimore, MD) was originally surveyed in the 1600-1700s under a system of warrants and patents (commonly known as ‘metes
and bounds’). A method for the reconstruction and mapping of warrant and patent properties is presented and used to map the
original property mosaic in the Gwynns Falls watershed. Using the mapped mosaic, the persistence of properties and property
lines in the current Gwynns Falls landscape is considered. The results of this research indicate that as in agricultural areas,
the original property lines in the Gwynns Falls watershed are persistent. At the same time, the results suggest that the property
mosaic in heavily urbanized/suburbanized areas is generally ‘reset.’ Further, trends in surveying technique, parcel size,
and settlement patterns cause property line density and property shape complexity to increase in the less urbanized upper
watershed. The persistence of original patterns may be damping expression of heterogeneity gradients in this urban landscape.
This spatial pattern of complexity in the original mosaic is directly opposite of hypothesized patterns of landscape heterogeneity
arising from urbanization. The technique reported here and the resulting observations are important for landscape pattern
studies in areas settled under unsystematic survey systems, especially the heavily urbanized areas of the eastern United States.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
47.
赵名茶 《干旱区资源与环境》1993,(Z1)
<正> 全球变暖问题已经是全世界关注的焦点,不仅各国科学家们进行了大量的研究,各国政府也耗费巨资组成了政府间专家组(IPCC,Intergovernmental panel on ClimateChange研究气候变化的影响。IPCC包括3个工作组,Ⅰ.科学分析工作组(Working 相似文献
48.
《干旱区资源与环境》1993,(Z1)
<正> The Ordos Plateau is a unified geographical region demarcated by the Yellow River's elbow section on the north and the Great Wall on the south, administratively comprisingthe whole Ih-Ju League of Inner Mongolia, part of Yulin Prefecture of Shaanxi Province,and part of Yanchi County of Ningxia. The unique sandy and denuded landscape of the pla- 相似文献
49.
50.
Improved understandings of the agricultural and range ecologies ofsemi-arid Africa require better information on the spatiotemporal distributionof domestic livestock across agropastoral landscapes. An empirical GIS-basedapproach was developed for estimating distributions of herded livestock acrossthree agropastoral territories (around 100 km2 each)over a two-year period. Algorithms developed from regression analyses of herdtracking data (with R2s 0.67) are used to transform a morecomprehensive but incomplete set of data generated from herders accounts oftheir herds grazing itineraries (400 herds following 6500 itineraries). Theresulting characterization registers 40 000 days of livestock activitiesacross694 land units (averaging 70 ha) over the study period. This studydemonstrates that rural producers knowledge of their daily extractionpracticescan be translated to fine-grained characterizations of extraction densitiesacross mixed landscapes. The spatiotemporal distribution of livestock that isrevealed by this approach diverges strongly from that predicted bycommonly-usedpoint-diffusion estimation procedures. Instead, the distribution reflects localpatterns of land use, topography, vegetation, settlements, and water points.Grazing and nongrazing times spent in land units are not spatially correlatedand the seasonality of grazing pressure is spatially variable. Therefore, theecological impacts of livestock grazing are spatially variable at fine scalesand there is a significant potential for livestock-mediated nutrient transfersacross agropastoral landscapes. The georeferenced data produced by thisapproachnot only will help evaluate the impact and sustainability of differentmanagement practices but also provides a strong empirical base for improvedspatial modeling of herded livestock.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献