Evaluating the relationship between drought and vegetation greenness in Chyulu-Amboseli Rangeland, Kenya

Remote sensing techniques have been widely used to monitor moisture-related vegetation conditions. Vegetation vigour response to drought however is complex and has not been adequately studied using satellite sensor data. This paper investigated the time lag response of vegetation to drought in Kenya’s Chyulu-Amboseli ecosystem based on Standardized Precipitation Index (SPI) derived from monthly precipitation data for the period January 2000-October 2016 downloaded from the Climate Hazards group InfraRed Precipitation with Stations and Normalized Difference Vegetation Index (NDVI) computed from Moderate Resolution Imaging Spectro-radiometer (MODIS) pre-processed images downloaded from the University of Natural Resources and Life Sciences (BOKU) database. Statistical analysis showed that drought severity increased over the study period while corresponding vegetation conditions degenerated. Results further revealed that the relationship between drought and vegetation greenness was significant (R2 = 0.6) with 2 months optimal lag. This calls for policy makers and programme managers to integrate the lag effect in measures to cope with drought in the rangelands.Keywords: Drought, Vegetation greenness, Chyulu-Amboseli, Statistical Analysis, Rangelan

An inventory of rangelands in part of the Broome Shire, Western Australia

The inventory of rangelands in part of the Broome Shire in Western Australia was undertaken by DAFWA between 1989 and 1990. It describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The survey of part of the Broome Shire covers about 8664km² of pastoral land in the Canning Basin region. It lies adjacent to the west coast of the Broome Shire, which is in the south-west of the Kimberley region of Western Australia. The survey area is dominated by extensive sandplains and dune fields which border the northern edge of the Great Sandy Desert. A smaller area of coastal plain occurs on the western edge of the survey area. Soils on the sandplain and dune fields are predominantly deep red sands and loamy sands. Coastal plain soils are light grey silty clays. Pastures are dominated by spinifex communities on the sandplain with halophytic species dominating pastures on the coastal plain. There are no permanent water courses in the area although there are several springs on the inland margin of the coastal plain. Stock are almost entirely dependent upon man-made watering points

Vegetation Outlook (VegOut): Predicting Remote Sensing–Based Seasonal Greenness

Accurate and timely prediction of vegetation conditions enhances knowledge-based decision making for drought planning, mitigation, and response. This is very important in countries that are highly dependent on rainfed agriculture. For example, studies show that remote sensing–based observations and vegetation condition prediction have great potential for estimating crop yields (Verdin and Klaver, 2002; Ji and Peters, 2003; Seaquist et al., 2005; Tadesse et al., 2005a, 2008; Funk and Brown, 2006), which in turn may help to address agricultural development and food security issues, as well as improve early warning systems. Many studies have demonstrated the value of Vegetation Indices (VIs), such as the Normalized Difference Vegetation Index (NDVI), calculated from satellite observations for assessing vegetation cover and conditions (Tucker et al., 1985; Roerink et al., 2003; Anyamba and Tucker, 2005; Seaquist et al., 2005), and such data have become a common source of information for vegetation monitoring. The term vegetation condition in this chapter refers to vegetation greenness or vegetation health, as inferred from canopy reflectance values measured by satellite observations (Mennis, 2001; Anyamba and Tucker, 2005). The vegetation greenness metric is commonly calculated from time-series NDVI (Reed et al., 1994) and represents the seasonal, time-integrated NDVI at a specific date, which has been shown to be representative of indicators of general vegetation health including net primary production (NPP) and green biomass (Tucker et al., 1985; Reed et al., 1996; Yang et al., 1998; Eklundh and Olsson, 2003; Hill and Donald, 2003). As a result, VIs and VI derivatives such as time-integrated VI can be used to characterize the temporal and spatial relationships between climate and vegetation and improve our understanding of the lagged relationship between climate (e.g., precipitation and temperature) and vegetation response (Roerink et al., 2003; Anyamba and Tucker, 2005; Seaquist et al., 2005; Camberlin et al., 2007; Groeneveld and Baugh, 2007). Quantitative descriptions of climate-vegetation response lags can then be used to identify and predict vegetation stress during drought

Long-term analysis of the asynchronicity between temperature and precipitation maxima in the United States Great Plains

Agriculture is a critical industry to the economy of the Great Plains (GP) region of North America and sensitive to change in weather and climate. Thus, improved knowledge of meteorological and climatological conditions during the growing season and associated variability across spatial and temporal scales is important. A distinct climate feature in the GP is the asynchronicity (AS) between the timing of temperature and precipitation maxima. This study investigated a long-term observational data set to quantify the AS and to address the impacts of climate variability and change. Global Historical Climate Network Daily (GHCN-Daily) data were utilized for this study; 352 GHCN-Daily stations were identified based on specific criteria and the dates of the precipitation and temperature maxima for each year were identified at daily and weekly intervals. An asynchronous difference index (ADI) was computed by determining the difference between these dates averaged over each decade. Analysis of daily and weekly ADI revealed two physically distinct regimes of ADI (positive and negative), with comparable shifts in the timing of both the maximum of precipitation and temperature over all six states within the GP examined when comparing the two different regimes. Time series analysis of decadal average ADI yielded moderate shifts (∼5 to 10 days from linear regression analysis) in ADI in several states with increased variability occurring over much of the study region

Deteriogenic flora of the Phlegraean Fields Archaeological Park: ecological analysis and management guidelines

Biodeterioration, the alteration caused by living organisms, on historical buildings and stone monuments is a well-known problem affecting two-thirds of the world’s cultural heritage. The study of the flora growing on wall surface is of particular importance for the assessment of the risk of biodeterioration of stone artifacts by vascular plants, and for maintenance planning. In this study, we investigate how rock type, exposure and inclination of the wall affect the biodeteriogenic flora at 13 sites of the Archaeological Park of the Phlegraean Fields located in the province of Naples, in southern Italy. For each site, we analysed randomly selected square areas with 2 × 2 m size, representing the different vegetation types in terms of vascular plant species cover. The total num - ber of plant species recorded was 129, belonging to 43 families. Erigeron sumatrensis, Sonchus tenerrimus and Parietaria judaica are the most commonly reported species, while Capparis orientalis is the species with the highest average coverage. Substrate type, exposure and surface inclination affect the floristic composition, with the average plant cover significantly higher on vertical surfaces and at western and southern expo - sure. All the main biodeteriogenic vascular plant species grow on more or less porous lythotype like yellow tufa, conglomerate and bricks. Finally, woody plants eradications methods are proposed by the tree cutting and local application of herbicides, to avoid stump and root sprouting and to minimize the dispersion of chemicals in the sur- rounding environment

Pilbara steer growth evaluation : 1994 - 1996

Growth potential of steers in the Pilbara - a summary. The trial was conducted over a range of conditions on three locations. The pasture type at Wyloo, the Ashburton River frontage, which is regarded as one of the most productive pasture types in the area, combined with conservative stocking, a fresh paddock and excellent seasonal conditions during 1995, gives us an indication of the District\u27s potential. In extrapolating any of these data to other cases, consideration must be given to adjustment bas

The Victorian Naturalist

v.114 (1997

Pasture condition guides for the Pilbara

These pasture condition guides are relevant to about 192 000 square kilometres of the Pilbara region of Western Australia. The rangeland of the Pilbara can be separated into 12 very broad pasture types. The ‘pasture type’ is not strictly a botanical classification because, in determining such a class of pastoral lands, the perennial plant species that contribute to stock production have an over-riding importance. Even so, each pasture type represents a broad group of similar vegetation associations or ‘site types’ which will have similar management requirements for pastoralism. The aim of this publication is to provide pastoralists with descriptions and condition statements for individual pasture types as a guide, based on land capability assessment, for management and sustainable use