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261.
针对地处四湖腹地的湖北省监利县果树资源利用率低及涝洼湿地的地理环境和生态条件 ,提出加快果树资源品种结构的调整 ,监北地势稍高 ,排灌方便的地方大力发展以猕猴桃为主的产业 ,同时利用架面下的行间土地套种蔬菜、瓜类作物、草莓、食用菌以及耐荫湿的中草药植物等立体生态农业的栽培模式 ,达到经济效益和生态效益的同步增长 ,与其相配套的栽培关键技术是采用地下通气排灌暗沟设施 ,重施有机质肥加磷肥 ;高畦壮苗定植 ;巧施追肥 ;适时排灌 ;树盘覆草保墒 ;人工辅助授粉和疏花疏果 相似文献
262.
Norman D. Folmar Arthur C. Miller Donald E. Woodward 《Journal of the American Water Resources Association》2007,43(3):829-838
Abstract: Many of the hydrologic methods that are used in engineering practice today resulted from the Spring Flood of 1936, which blanketed the Northeastern portion of the United States. Because of the flood damage that was caused by this rainfall‐snowmelt event, many federal agencies including the U.S. Army Corp of Engineers and the Soil Conservation Service (SCS) implemented the hydrologic theories that were available in the literature at this time and developed hydrologic procedures for design flow estimation. Sherman had recently published his unit hydrograph theory in 1932, and later in 1938 Snyder, who had been charged by the Water Resource Council to develop a synthetic unit hydrograph, published his famous paper. The SCS unit hydrograph theory was developed by Victor Mockus in the late 1950s. Most if not all of the theories at that time reported the rainfall‐runoff process for floods as a surface phenomenon, and as such those theories all required some type of a timing parameter to estimate watershed response time. This article documents the development of the SCS lag equation. 相似文献
263.
264.
江淮地区极端气候事件的时空变化特征 总被引:3,自引:1,他引:3
利用1951—2003年的温度和降水资料,研究了江淮地区极端气候事件的空间结构及年代际变化特征。结果发现:(1)气候变暖影响了极端气候事件的变化,这种影响是由气候平均值和方差的共同变化引起的。(2)气候变暖加速了水分的循环过程,导致20世纪90年代以来江淮地区旱涝频率和强度加大,强降水事件增加;冬季极端最低温度升高,低温日数减少;夏季极端最高温度和高温日数开始回升。(3)从极端事件分布的区域变化来看,气候变暖对淮北的影响最大,使这个脆弱性本来就很严重的区域变得更加脆弱。 相似文献
265.
从人地关系理论出发以土地利用变化为切入点通过野外调查和遥感动态监测对干旱区绿洲土地覆盖变化规律进行了研究.在考察数据和对遥感图像的分类结果的评价的基础上对干旱区绿洲土地利用/土地覆盖空间动态变化进行规律性分析提出只有协调人地关系、加强区域地理建设才是使干旱区绿洲地区避免荒漠化的唯一道路. 相似文献
266.
267.
旅游业作为“朝阳产业”,越来越显示出其在国民经济中的重要性。立足辽东地区的旅游资源实际,对该地区旅游发展态势及旅游产业对金融的需求进行了详尽的分析,在此基础上提出了金融支持旅游产业发展并以此来提升金融竞争力的主要对策。 相似文献
268.
Maintaining Volunteer Commitment to Local Watershed Initiatives 总被引:1,自引:0,他引:1
Australia's Landcare program is advanced as a successful international example of local watershed groups and governments working
together to improve natural resource management. One of the aspects considered critical in the success of watershed groups
is engaging widespread participation. This paper draws on two regional surveys that explored burnout, or loss of engagement,
among Landcare participants in the state of Victoria using the Maslach Burnout Inventory. Survey findings indicated that a
large proportion of respondents were experiencing high burnout in terms of low personal accomplishment and suggested that
there was potential for burnout to increase. The authors suggest that the expectations of watershed groups must be based around
a realistic assessment of the capacity for volunteer groups to deliver improved environmental and social outcomes. 相似文献
269.
The Cache River of southernmost Illinois is used as a case study for developing and demonstrating an approach to quantitatively
link (1) national agricultural policy and global agricultural markets, (2) landowner's decisions on land use, (3) spatial
patterns of land use at a watershed scale, and (4) hydrologic impacts, thus providing a basis to predict, under a certain
set of circumstances, the environmental consequences of economic and political decisions made at larger spatial scales. The
heart of the analysis is an estimation, using logistic regression, of the affect of crop prices and Conservation Reserve Program
(CRP) rental rates on farmland owner's decisions whether to reenroll in the CRP or return to crop production. This analysis
shows that reasonable ranges for crop prices (80%–150% of 1985–1995 values) and CRP rental rates (0–125% of 1985–1995 rates)
result in a range of 3%–92% of CRP lands being returned to crop production, with crop prices having a slightly greater effect
than CRP rental rates. Four crop price/CRP rental rate scenarios are used to display resulting land-use patterns, and their
effect on sediment loads, a critical environmental quality parameter in this case, using the agricultural non point source
(AGNPS) model. These scenarios demonstrate the importance of spatial pattern of land uses on hydrological and ecological processes
within watersheds. The approach developed can be adapted for use by local governments and watershed associations whose goals
are to improve watershed resources and environmental quality. 相似文献
270.
Optimum natural resource management and biodiversity conservation are desirable goals. These, however, often exclude each
other, since maximum economic benefits have promoted drastic reductions in biodiversity throughout the world. This dilemma
confronts local stakeholders, who usually go for maximizing economic inputs, whereas other social (e.g., academic) sectors
are favor conservation practices. In this paper we describe the way two scientific approaches—landscape and participatory
research—were used to develop sound and durable land use scenarios. These two approaches included expert knowledge of both
social and environmental conditions in indigenous communities. Our major emphasis was given to detect spatially explicit land
use scenarios and capacity building in order to construct a decision support system operated by stakeholders of the Comunidad
Indigena de Nuevo San Juan Parangaricutiro in Mexico. The system for decision-making was fed with data from inventories of
both abiotic and biotic biodiversity components. All research, implementation, and monitoring activities were conducted in
close collaboration with members of the indigenous community. As a major result we obtained a number of forest alternative
uses that favor emerging markets and make this indigenous community less dependent on a single market. Furthermore, skilled
members of the community are now running the automated system for decision-making. In conclusion, our results were better
expressed as products with direct benefits in local livelihoods rather than pure academic outputs. 相似文献