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1.
In this paper the problem of energy consumption and environment in the birdhouse is introduced and the reconstructive measures aiming at energy savings are recommended. The measures include the limitation of temperature region, reconstruction of the building envelop and using the sunny board at the south side of the birdhouse roof. Finally, the energy efficiency of the reconstructive project is estimated.  相似文献   
2.
为研究农业技术水平和自然禀赋对农业碳排放和碳汇的影响,通过修正后的农业碳补偿测算方法,计算得到2007—2016年长江经济带各省(市)的农业碳补偿额并进行对比分析。结果表明:江西和湖南的农业碳排放冗余量均为零值,农业技术水平较高,浙江和云南的农业碳排放冗余量较高,均值分别达到237.18万t和175.13万t,农业技术水平落后;浙江、江西、四川和云南的年均调整系数小于1,农业自然资源禀赋高于长江经济带的整体水平;修正后浙江和云南的碳补偿额由正数变为负数,表明这两个省从碳受偿地区变为碳支付地区,上海、江苏、安徽、湖北、湖南、重庆、贵州农业碳补偿额比修正前有所增加,江西和四川农业碳补偿额则比修正前减少。长江经济带各省域应加强农业自然禀赋的建设,提高生态背景值,增强其农业生态系统的碳汇功能,加快实现长江经济带生态补偿公平价值,并提升生态资源利用的地区公平性。  相似文献   
3.
Crop production in Georgia and the Southeastern U.S. can be limited by water. Highly-weathered, drought-prone soils are susceptible to runoff and erosion. Rainfall patterns generate runoff producing storms followed by extended periods of drought during the crop growing season. Thus, supplemental irrigation is often needed to sustain profitable crop production. Increased water retention and soil conservation would efficiently improve water use and reduce irrigation amounts/costs and sedimentation, and sustain productive farm land, thus improving producer's profit margin. Soil amendments, such as flue gas desulfurization (FGD) gypsum, have been shown to retain rainfall and/or irrigation water through increased infiltration while decreasing runoff (R) and sediment (E). Objectives were to quantify rainfall partitioning and sediment delivery improvements with surface applied FGD gypsum from an Ultisol managed to conventional till (CT) and to assess the feasibility of using FGD gypsum on agricultural land in southern Georgia. A field study (Faceville loamy sand, Typic Kandiudult) was established (2006, 2007) near Dawson, GA managed to CT, irrigated cotton (Gossypium hirsutum L.). FGD gypsum application rates evaluated were 0, 1.1, 2.2, 4.5, and 9 Mg ha− 1. Gypsum treatments and simulated rainfall (50 mm h− 1 for 1 h) were applied to 2-m wide × 3-m long field plots (n = 3). Runoff and E were measured from each 6-m2 plot (slope = 1%). FGD gypsum plots averaged 26% more infiltration (INF), 40% less R, 58% less E, 27% lower maximum R rates (Rmax), and 2 times lower maximum E rates (Emax) than control plots. Values of INF and water for crop use increased, and R, E, Rmax, and Emax decreased as FGD gypsum application rate increased. Values of INF, R, E, Rmax, and Emax for 9 Mg ha− 1 plots were as much as 17% greater, 35% less, 1.9 times less, 35% less, and 1.9 times less than those from other FGD gypsum plots, respectively; and 40% greater, 40% less, 2.2 times less, 52% less, and 2.9 times less than those from control plots, respectively. Applying FGD gypsum to agricultural lands is a cost-effective management practice for producers in Georgia that beneficially impacts natural resource conservation, producer profit margins, and environmental quality. Agriculture in the Southeast provides a viable market for the electric power industry to convert disposal costs of FGD gypsum into a profitable commodity.  相似文献   
4.
江苏省土地资源禀赋度空间变化研究   总被引:3,自引:0,他引:3  
皮啸菲  周生路  吴绍华 《土壤》2010,42(4):652-657
本文从土地数量、质量、结构和效益等方面构建了土地资源禀赋度评价指标体系,并采用多边形综合指标法对江苏全省各市县土地资源禀赋现状及空间变化进行了研究。结果表明:①江苏省土地资源禀赋度差异显著,呈现由南向北先递减后递增的规律,总体上苏南好于苏北好于苏中;②1996—2006十年间各市县土地资源禀赋度总体有所下降;③今后应根据区域特点,采取针对措施,提高区域土地资源禀赋度。  相似文献   
5.
Worldwide growing water scarcity has increased the call for economic instruments to stimulate rational water use in agriculture. Furthermore, cost-recovery is now widely accepted as a cornerstone of sustainable water management. In many developing countries, where agricultural water use is often still subsidised, water pricing policies are developed for allocating water efficiently and achieving sustainability of water systems. However, the impacts of water pricing policies on irrigation water use and on farm production systems is mostly unknown. We introduce an innovative two-stage methodology that allows estimating these effects at farm level. Applying the method to small-scale irrigators in South Africa, we show that water demand is quite responsive even to small changes in water price. In addition, the introduction of a water price significantly decreases farm profit. This appears to be a problem primarily for the poorer farmers.  相似文献   
6.
The Central Asian countries face high water scarcity due to aridity and desertification but excess water is often applied to the main irrigated crops. This over-irrigation contributes to aggravate water scarcity problems. Improved water saving irrigation is therefore required, mainly through appropriate irrigation scheduling. To provide for it, after being previously calibrated and validated for cotton in the Fergana region, the irrigation scheduling simulation model ISAREG was explored to simulate improved irrigation scheduling alternatives. Results show that using the present irrigation scheduling a large part of the applied water, averaging 20%, percolates out of the root zone. Several irrigation strategies were analyzed, including full irrigation and various levels of deficit irrigation. The analysis focused a three-year period when experiments for calibration and validation of the model were carried out, and a longer period of 33 years that provided for an analysis considering the probabilities of the demand for irrigation water. The first concerned a wet period while the second includes a variety of climatic demand conditions that provided for analyzing alternative schedules for average, high and very high climatic demand. Results have shown the importance of the groundwater contribution, mainly when deficit irrigation is applied. Analyzing several deficit irrigation strategies through the respective potential water saving, relative yield losses, water productivity and economic water productivity, it could be concluded that relative mild deficits may be adopted. Contrarily, the adoption of high water deficit that produce high water savings would lead to yield losses that may be economically not acceptable.  相似文献   
7.
为探究农户资本禀赋、感知价值对其秸秆收集受偿意愿的影响及作用机制,基于布迪厄社会实践理论构建分析框架,利用湖北省黄冈市秸秆综合利用重点县684份农户调查数据,使用二元Logit和OLS模型实证分析农户资本禀赋、感知价值对其秸秆收集受偿意愿的影响。结果表明:1)愿意参与秸秆收集生态补偿的农户占总样本的90.35%,其最小受偿额度平均值为791.45元/hm2;2)资本禀赋对农户秸秆收集生态补偿参与意愿有显著正向影响,对受偿额度有显著负向影响;3)感知价值对农户秸秆收集生态补偿参与意愿和受偿额度均有显著正向影响;4)感知价值在资本禀赋与秸秆收集生态补偿参与意愿之间具有中介效应,中介效应量为0.289;感知价值在资本禀赋与秸秆收集受偿额度之间具有遮掩效应,遮掩效应量为0.225。因此,为鼓励农户的秸秆收集行为,应加快完善秸秆收集生态补偿措施并分层分阶段推进,多渠道提升农户资本禀赋的同时提高农户对秸秆收集行为的感知价值。  相似文献   
8.
刘艳婷  陈美球 《农学学报》2020,36(1):160-164
构建科学有效的宅基地流转机制是一个迫切需要解决的基础性课题。笔者利用江西省456户农户的实际调查数据,运用Logit回归模型研究家庭经济禀赋、政策认知对农户宅基地流转意愿的影响。研究结果表明:家庭经济禀赋中非农收入比重、家庭存款、家庭人均年收入对农户宅基地流转意愿具有显著正向影响;政策认知中“一户一宅”认知、流转规定认知程度对农户宅基地流转意愿具有显著负向影响。为此,应进一步提高农户非农就业机会,改善农民务工经商的就业环境、应加快制定“一户一宅”的配套制度,构建更加合理和更具有操作性的宅基地流转政策体系。  相似文献   
9.
甘肃省森林资源禀赋与贫困关系的量化研究   总被引:2,自引:0,他引:2  
本文以SPSS统计软件中的相关分析方法和回归分析方法为工具,以森林资源丰富县和贫困县的相关数据为指标,分析了甘肃省森林资源禀赋与贫困之间的关系,得出的结论是森林资源禀赋与贫困之间无相关性。  相似文献   
10.
王鑫  马凌 《安徽农业科学》2014,(34):12330-12332,12335
我国的第一代农民工已经到了知天命的年龄,但是他们未能安享晚年,养老问题将集中爆发。首先从城镇职工养老保险的参保率低退保率高、新农保的参保率高保险待遇低、超龄务工三个方面分析了第一代农民工的境遇,其次从政府、企业、第一代农民工个体三个责任主体剖析了其深层原因,然后对第一代农民工的其他养老方式的可行性进行了分析,最后基于第一代农民工的不同去向及主要收入来源提出了对策建议。  相似文献   
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