13,024 research outputs found
A Multi-Temporal Object-Based Image Analysis to Detect Long-Lived Shrub Cover Changes in Drylands
Climate change and human actions condition the spatial distribution and structure of vegetation, especially in drylands. In this context, object-based image analysis (OBIA) has been used to monitor changes in vegetation, but only a few studies have related them to anthropic pressure. In this study, we assessed changes in cover, number, and shape of Ziziphus lotus shrub individuals in a coastal groundwater-dependent ecosystem in SE Spain over a period of 60 years and related them to human actions in the area. In particular, we evaluated how sand mining, groundwater extraction, and the protection of the area affect shrubs. To do this, we developed an object-based methodology that allowed us to create accurate maps (overall accuracy up to 98%) of the vegetation patches and compare the cover changes in the individuals identified in them. These changes in shrub size and shape were related to soil loss, seawater intrusion, and legal protection of the area measured by average minimum distance (AMD) and average random distance (ARD) analysis. It was found that both sand mining and seawater intrusion had a negative effect on individuals; on the contrary, the protection of the area had a positive effect on the size of the individualsâ coverage. Our findings support the use of OBIA as a successful methodology for monitoring scattered vegetation patches in drylands, key to any monitoring program aimed at vegetation preservation
Visible and near infrared spectroscopy in soil science
This chapter provides a review on the state of soil visibleânear infrared (visâNIR) spectroscopy. Our intention is for the review to serve as a source of up-to date information on the past and current role of visâNIR spectroscopy in soil science. It should also provide critical discussion on issues surrounding the use of visâNIR for soil analysis and on future directions. To this end, we describe the fundamentals of visible and infrared diffuse reflectance spectroscopy and spectroscopic multivariate calibrations. A review of the past and current role of visâNIR spectroscopy in soil analysis is provided, focusing on important soil attributes such as soil organic matter (SOM), minerals, texture, nutrients, water, pH, and heavy metals. We then discuss the performance and generalization capacity of visâNIR calibrations, with particular attention on sample pre-tratments, co-variations in data sets, and mathematical data preprocessing. Field analyses and strategies for the practical use of visâNIR are considered. We conclude that the technique is useful to measure soil water and mineral composition and to derive robust calibrations for SOM and clay content. Many studies show that we also can predict properties such as pH and nutrients, although their robustness may be questioned. For future work we recommend that research should focus on: (i) moving forward with more theoretical calibrations, (ii) better understanding of the complexity of soil and the physical basis for soil reflection, and (iii) applications and the use of spectra for soil mapping and monitoring, and for making inferences about soils quality, fertility and function. To do this, research in soil spectroscopy needs to be more collaborative and strategic. The development of the Global Soil Spectral Library might be a step in the right direction
Misc. Pub. 91-1
I submit herewith the annual report of the Agricultural and Forestry Experiment
Station, School of Agriculture and Land Resources Management, University of Alaska
Fairbanks, for the period ending December 31,1990. This is done in accordance with an act of the Congress, approved March 2,1887, entitled "An act to establish Agricultural Experiment Stations, in connection with the Agricultural Colleges established in the several states under the provisions of an act approved July 2,1862, and under the acts supplementary thereto," and also of the act of the Alaska Territorial Legislature, approved March 12,1935, accepting the provisions of the act of Congress. James V. Drew, DirectorStatement of Purpose -- Plant and Animal Sciences -- Forest Sciences -- Resources Management -- Financial Statement -- Publications - Staf
GIS Applications in Agronomy
Agronomy is a branch of agriculture that deals with soil and crop. Soil varies in space and is responsible for variation in the growth and yield of crops on the field. This variation in the yields of crops planted and monitored on the same parcel of land under the same environmental conditions has been a great concern to farmers. Spatial variations of soil nutrients status, as caused by topography, soil texture and management practices, have been observed across the fields. Hence, the need to separate the field into site specific management units using geographical information systems (GIS) for effective soil and crop management in order to obtain optimum productivity. Over the years, field sizes, farming direction, locations of fences, rotations and fertility programmes have changed the nutritional status of the farms. Consequently, the productivity of the soil has equally been affected. In spite of these factors, conventional agriculture treats an entire field uniformly with respect to the application of fertiliser, pesticides, soil amendments and other chemical application. The use of GIS will help farmers to overcome over- or under-applications of fertiliser and other agrochemical applications. The potential of GIS application in agronomy is obviously large. However, the GIS user community in the field of agronomy is rather small compared to other business sectors. To advance the use of GIS in agronomic studies, this Chapter in book tends to explore the applications of GIS to some fields in agronomy
Organic residues - a resource for arable soils
An increased recirculation of urban organic residues to arable soils has several environmental benefits, but there is a need for reliable test systems to ensure that soil quality is maintained. In this thesis, soil microbial, chemical and physical properties were included in an integrated evaluation to reflect the positive and negative effects of amending arable soils with organic residues. Efficient statistical tools and methods to describe intrinsic spatial variation are important when evaluating soil data. A new method was developed, combining near infrared reflectance (NIR) spectroscopy with principal component analysis (PCA). The first principal component (PC1) of NIR data described spatial soil variation better than the conventional soil variables total carbon, clay content and pH. A long-term field trial was established in which the soil was amended annually with organic residues (compost, biogas residues, sewage sludge) and fertilizers (pig manure, cow manure and mineral fertilizer, NPS). Annual measurements of soil and crop quality as well as yield revealed that biogas residues performed best among the organic residues. It improved several important microbiological properties, such as substrate-induced respiration (SIR) and potential ammonium oxidation (PAO), and it compared well with mineral fertilizer in terms of grain quality and harvest yield. Altogether, the results from the field trial showed no negative effects from any of the organic residues. Short- and moderately long-term effects of wood ash and compost on potential denitrification activity (PDA) and PAO were evaluated in a laboratory incubation experiment. Wood ash application had a profound toxic effect on PDA both in the short- and long-term. This toxic effect was mitigated when compost was added to the soil
Integrated nutrient management, soil fertility, and sustainable agriculture: current issues and future challenges
The challenge for agriculture over the coming decades will be to meet the world's increasing demand for food in a sustainable way. Declining soil fertility and mismanagement of plant nutrients have made this task more difficult. In this brief, Peter Gruhn, Francesco Goletti, and Montague Yudelman point out that as long as agriculture remains a soil-based industry, major increases in productivity are unlikely to be attained without ensuring that plants have an adequate and balanced supply of nutrients. They call for an Integrated Nutrient Management approach to the management of plant nutrients for maintaining and enhancing soil, where both natural and man-made sources of plant nutrients are used. The key components of this approach are described; the roles and responsibilities of various actors, including farmers and institutions, are delineated; and recommendations for improving the management of plant nutrients and soil fertility are presented.Plant nutrients., Soil fertility., Crops Nutrition., Sustainable agriculture.,
A Novel Hybrid AI Federated ML/DL Models for Classification of Soil Components
The soil is the most fundamental component for the survival of any living thing that can be found on this planet. A little less than 41 percent of Indians are employed in agriculture, which accounts for approximately 19 percent of the country's gross domestic product. As is the case in every other industry, researchers and scientists in this one are exerting a lot of effort to enhance agricultural practices by utilising cutting-edge methods such as machine learning, artificial intelligence, big data, and so on. The findings of the study described in this paper are predicated on the assumption that the method of machine learning results in an improvement in the accuracy of the prediction of soil chemical characteristics. The correlations that were discovered as a result of this research are essential for comprehending the comprehensive approach to predicting the soil attributes using ML/DL models. A number of findings from previous study have been reported and analysed. A state of the art machine learning algorithm, including Logistic Regression, KNN, Support Vector Machine and Random Forest are implemented and compared. Additionally, the innovative Deep Learning Hybrid CNN-RF and VGG-RNN Model for Categorization of Soil Properties is also implemented along with CNN. An investigation into the significance of the selected category for nutritional categorization revealed that a multi-component technique provided the most accurate predictions. Both the CNN-RF and VGG-RNN models that were proposed were successful in classifying the soil with average accuracies of 95.8% and 97.9%, respectively, in the test procedures. A study was carried out in which the CNN-RF model, the VGG-RNN model, and five other machine learning and deep learning models were compared. The suggested VGG-RNN model achieved superior accuracy of classification and real-time durability, respectively
Development of an Adaptive Environmental Management System for Lejweleputswa District: A Participatory Approach through Fuzzy Cognitive Maps
Published ThesisEnvironmental pollution caused by mines within the district of Lejweleputswa in Free
State is a major contributor to health issues and the inability to grow crops within the
mining communities. Mining industries continue to develop environmental
management systems/plans to mitigate the impact their operations has on the society.
Even with these plans, there are still issues of environmental pollution affecting the
society. Though there are Information Communication and Technology (ICT) based
pollution monitoring solutions, their use is dismal due to lack of appreciation or
understanding of how they disseminate information. Furthermore, non-adopting
community members are being regarded as inherently conservative or irrational, but
these community members argue that the recommendations and technologies brought
to them are not always appropriate to their circumstances. There was concern that
local peopleâs knowledge of their environment, farming systems, and their social as
well as economic situation had been ignored and underestimated when ICTs solutions
are being implemented (Warburton & Martin, 1999). Another challenge is that there is
no station to monitor pollution for small communities such as Nyakallong in the district.
This result in mining communities depending on their own local knowledge to observe and monitor mining related environmental pollution. However, this local knowledge
has never been tested scientifically or analysed to recognize its usability or
effectiveness. Mining companies tend to ignore this knowledge from the communities
as it is treated like common information with no much scientific value. As a step
towards verifying or validating this local knowledge, fuzzy cognitive maps were used
to model, analyse and represent this linguistic local knowledge.
Although this local knowledge assists in mitigating environmental pollution,
incorporating it with scientific knowledge will improve its relevance, trustworthiness
and acceptability by majority of community members and policy-makers. Information
and Communication Technologies (ICTs) can accelerate this integration; this is the
focus of this research. The increased usages of Information Technology being witnessed today makes it the
most important factor for the world to depend on for solutions to many of todayâs and
tomorrowâs problems. These solutions make use of various forms for dissemination
purposes, one of the most versatile dissemination device is a mobile phone since majority of the worldâs population do own a mobile phone. In this way information is
easily accessible by almost everyone that needs it.
A novel environmental management solution was designed to work within the mining
communities of Lejweleputswa. The research started off by designing a unique
integration framework that creates the much-needed link between local knowledge
and scientific knowledge. The framework was then converted into an adaptable
environmental pollution management system prototype made up of three components;
(1) gathering environmental pollution knowledge; (2) environmental monitoring and;
(3) environmental dissemination and communication. To achieve sustainability,
relevance and acceptability, local knowledge was integrated in each of the three
components while mobile phones were used as both input and output devices for the
system. In order to facilitate collection and conservation of local knowledge on
environmental monitoring, an elaborate android-based mobile application was
developed. Wireless sensor-based gas sensor boards were acquired, and deployed
as a compliment to conventional monitoring stations, they were used to gather
scientific knowledge. To allow for public access to the systemâs data, a web portal and an SMS-based component were also implemented. In order to collect local knowledge
from community, a case study of Nyakallong community in Lejweleputswa was carried
out. On completion of the system prototype, it was evaluated by participants from the
community; 90% of respondents gave a score of âexcellent â
Spatial aspects of the design and targeting of agricultural development strategies:
Two increasingly shared perspectives within the international development community are that (a) geography matters, and (b) many government interventions would be more successful if they were better targeted. This paper unites these two notions by exploring the opportunities for, and benefits of, bringing an explicitly spatial dimension to the tasks of formulating and evaluating agricultural development strategies. We first review the lingua franca of land fragility and find it lacking in its capacity to describe the dynamic interface between the biophysical and socioeconomic factors that help shape rural development options. Subsequently, we propose a two-phased approach. First, development strategy options are characterized to identify the desirable ranges of conditions that would most favor successful strategy implementation. Second, those conditions exhibiting important spatial dependency â such as agricultural potential, population density, and access to infrastructure and markets â are matched against a similarly characterized, spatially-referenced (GIS) database. This process generates both spatial (map) and tabular representations of strategy-specific development domains. An important benefit of a spatial (GIS) framework is that it provides a powerful means of organizing and integrating a very diverse range of disciplinary and data inputs. At a more conceptual level we propose that it is the characterization of location, not the narrowly-focused characterization of land, that is more properly the focus of attention from a development perspective. The paper includes appropriate examples of spatial analysis using data from East Africa and Burkina Faso, and concludes with an appendix describing and interpreting regional climate and soil data for Sub-Saharan Africa that was directly relevant to our original goal.Spatial analysis (Statistics), Agricultural development., Burkina Faso., Africa, Sub-Saharan.,
- âŠ