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31.
Erosion and deposition rates were quantified in a vineyard context (Languedoc, France) using a method based on vine-stock bio-markers. The within-field spatial structure of erosion (Field Erosive State) was described based on maps of “unearthing” height of vine-stock.  相似文献   
32.
Summary In the 25-year-old vineyard of a farm near the Maremma National Park (Central Italy), replicate plots were established with a mulch of Trifolium subterraneum L. or cultivation and two levels of fertilizer. The mai objective of this research was to analyse responses by soil invertebrates and nutrients after introducing a herbaceous component into the system; the yield was also considered. The greater availability of organic substrate and the reduced cultivation as a result of green mulching increased the soil mesofauna biomass, especially detritivores. With time, a significant difference became evident between the populations of invertebrates present in the mulched plots and those in the cultivated plots. Over 2 years, most nutrients (Ca, K, P, and N) were significantly increased in the mulched plots compared to the cultivated plots. Grape yields were consistently higher in the bare plots. No significant differences were found in fertilizer effects.  相似文献   
33.
An evapotranspiration (ET) model for sparsely vegetated canopies under partial root-zone irrigation (PRI) was developed and tested using measurements from a vineyard in the arid region of northwest China. This model (PRI-ET) was mainly based on the Shuttleworth–Wallace (S-W) model and took into consideration the differences in soil water content between furrow-irrigation ditch and ridge under the PRI scheme and variable canopy shading over the surface. Estimates of ET and its components (plant transpiration and soil evaporation) by the PRI-ET and S-W models were compared to ET, plant transpiration and soil evaporation measured by Bowen ratio–energy balance, heat-pulse sap flow sensor and micro-lysimeter, respectively. The PRI-ET model can estimate the vineyard ET and its components more accurately than the S-W model, indicating that the PRI-ET model is suitable for estimating vineyard ET under PRI.  相似文献   
34.
吴彬  赵文娟 《安徽农业科学》2017,45(36):105-107
宁夏贺兰山东麓葡萄产地多年使用滴灌进行农业生产,导致该区域的土壤次生盐渍化。分析灌溉对土壤的危害,指出非生育期防治次生盐渍化的方向,可为该区域土壤次生盐渍化的防治提供理论依据。  相似文献   
35.
宁夏贺兰山东麓属大陆性干旱半干旱气候,干燥少雨,具备生产优质酿酒葡萄的气候条件,同时具有天然的生态敏感性。葡萄园作为一个传统的典型农业生态系统,该区域内的生物多样性水平受当地生态气候、生产技术和管理模式等因素影响。本文以夏桐葡萄园作为调查样地,对植物和昆虫的生物多样性现状进行调查分析和科学评估,提出了葡萄园种植过程中提高生物多样性水平的相关建议与管理措施,以期为贺兰山东麓产区生态环境保护和生物多样性提升提供指导意见,助力葡萄酒产业可持续高质量发展。  相似文献   
36.
The goal of this study was to test the usefulness of high-spatial resolution information provided by airborne imagery and soil electrical properties to define plant water restriction zones within-vineyards. The main contribution of this is to propose a study on a large area representing the regions’ vineyard diversity (different age, different varieties and different soils) located in southern France (Languedoc-Roussillon region, France). Nine non-irrigated plots were selected for this work in 2006 and 2007. In each plot, different zones were defined using the high-spatial resolution (1 m2) information provided by airborne imagery (Normalised Difference Vegetation Index, NDVI). Within each zone, measurements were conducted to assess: (i) vine water status (Pre-dawn Leaf Water Potential, PLWP), (ii) vine vegetative expression (vine trunk circumference and canopy area), (iii) soil electrical resistivity and, (iv) harvest quantity and quality. Large differences were observed for vegetative expression, yield and plant water status between the individual NDVI-defined zones. Significant differences were also observed for soil resistivity and vine trunk circumference, suggesting the temporal stability of the zoning and its relevance to defining vine water status zones. The NDVI zoning could not be related to the observed differences in quality, thus showing the limitations in using this approach to assess grape quality under non-irrigated conditions. The paper concludes with the approach that is currently being considered: using NDVI zones (corresponding to plant water restriction zones) in association with soil electrical resistivity and plant water status measurements to provide an assessment of the spatial variability of grape production at harvest.  相似文献   
37.
Cover crops are often planted in between vineyard rows to reduce soil erosion, increase soil fertility, and improve soil structure. Roots of both grapevines and cover crops form mutualistic symbioses with arbuscular mycorrhizal (AM) fungi, and may be interconnected by AM hyphae. To study nutrient transfer from cover crops to grapevines through AM fungal links, we grew grapevines and cover crops in specially designed containers in the greenhouse that restricted their root systems to separate compartments, but allowed AM fungi to colonize both root systems. Leaves of two cover crops, a grass (Bromus hordeaceus) and a legume (Medicago polymorpha), were labeled with 99 atom% 15N solution for 24 h. Grapevine leaves were analyzed for 15N content 2, 5, and 10 days after labeling. Our results showed evidence of AM fungi-mediated 15N transfer from cover crops to grapevines 5 and 10 days after labeling. N transfer was significantly greater from the grass to the grapevine than from the legume to the grapevine. Possible reasons for the differences between the two cover crops include lower 15N enrichment in legume roots, higher biomass of grass roots, and/or differences in AM fungal community composition. Further studies are needed to investigate N transfer from grapevines to cover crops and to determine net N transfer between the two crops throughout their growing seasons, in order to understand the significance of AM fungi-mediated interplant nutrient transfers in the field.  相似文献   
38.
Grapevines are extensively grown in the arid region of China, but little information is available on the diurnal, seasonal and interannual variability of vineyard evapotranspiration (ET). To address this question, two vineyards in the arid region of northwest China were taken as an example to study the variation of ET using Bowen ratio-energy balance method in 2005-2008. Results indicate that the Bowen ratio method provided accurate estimate of vineyard ET as the instrument was correctly installed. Irrigation and rainfall increased daily ET by 38 and 175%, respectively, but frost decreased it by 32%. Daily ET had a maximum value of 1.6-3.5 mm/d at the berry development stage, and a minimum value of 0.8-1.7 mm/d at the early and later stages. The total ET was 226-399 mm over the growing season. The ratio of transpiration to evapotranspiration was 0.52 and the modified crop coefficient (Kcm) was 0.71-0.88 (except 2005) over the whole growing stage. Larger interannual difference of ET and Kcm mainly resulted from the difference of irrigation and rainfall between different years.  相似文献   
39.
黄庆南  李克俭  曾文波  章帆 《安徽农业科学》2011,39(21):13100-13102
根据葡萄园环境的监测需求,提出一种无线传感器网络的葡萄园环境参数监测系统,对其无线网关的软硬件进行设计。网关采用ZigBee和GPRS无线传输技术,以ARM9微处理器S3C2410为控制核心,基于嵌入式Linux的操作系统开发,实现数据监测节点与远程监测中心的双向通信。测试结果表明,网关的系统稳定可靠,对葡萄园环境的远程监测具有一定的参考价值。  相似文献   
40.
Spatially distributed hydrological modelling is required to understand and predict erosion, flooding and pollution risks that affect the vine cultivated Mediterranean environment. Previous field studies have demonstrated the dominant influence of soil surface features on overland flow and they therefore constitute an essential input to the hydrological model. In this paper we propose a remote sensing based method to map vineyard soil surface features with a spatial and temporal resolution appropriate for integration into the model. Our goal was to classify each soil surface portion in accordance with a pre-established, field measured infiltration capacity based typology. The radiometric characteristics of the classes of this typology were measured in the field and their Bi-directional Reflectance Distribution Function (BRDF) was modelled. Vineyard sunlit soil surface pixels were automatically extracted from high spatial resolution scanned aerial colour photographs Wassenaar et al., 2001 and Wassenaar et al., 2002. These pixels are radiometrically classified by comparison of their reflectance with BRDF-based reflectance predictions of each soil surface type for the specific illumination and viewing geometry of the pixel.The results show that most hydrological soil surface classes have distinct bi-directional radiometric properties. For one given geometric configuration however, the predicted reflectance ranges of some classes can considerably overlap (tilled soils and stone layers for example), while others can always unambiguously be identified (bare soil crusts, surfaces covered for more than 50% by weed or litter).We conclude that our fuzzy classification approach and the simple radiometric information used, allow us to identify the majority of the hydrological surface types. The method can easily be transposed in time and space. Its performance quite strongly depends on the radiometric and geometric accuracy of the input data. Significant improvements in soil surface classification precision are expected from considering spatial context information and monitoring the soil surface evolution.  相似文献   
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