Mapping Spatiotemporal Changes in Vegetation Growth Peak and the Response to Climate and Spring Phenology over Northeast China

Global climate change has led to significant changes in seasonal rhythm events of vegetation growth, such as spring onset and autumn senescence. Spatiotemporal shifts in these vegetation phenological metrics have been widely reported over the globe. Vegetation growth peak represents plant photosynthesis capacity and responds to climate change. At present, spatiotemporal changes in vegetation growth peak characteristics (timing and maximum growth magnitude) and their underlying governing mechanisms remain unclear at regional scales. In this study, the spatiotemporal dynamics of vegetation growth peak in northeast China (NEC) was investigated using long-term NDVI time series. Then, the effects of climatic factors and spring phenology on vegetation growth peak were examined. Finally, the contribution of growth peak to vegetation production variability was estimated. The results of the phenological analysis indicate that the date of vegetation green up in spring and growth peak in summer generally present a delayed trend, while the amplitude of growth peak shows an increasing trend. There is an underlying cycle of 11 years in the vegetation growth peak of the entire study area. Air temperature and precipitation before the growing season have a small impact on vegetation growth peak amplitude both in its spatial extent and magnitude (mainly over grasslands) but have a significant influence on the date of the growth peak in the forests of the northern area. Spring green-up onset has a more significant impact on growth peak than air temperature and precipitation. Although green-up date plays a more pronounced role in controlling the amplitude of the growth peak in forests and grasslands, it also affects the date of growth peak in croplands. The amplitude of the growth peak has a significant effect on the inter-annual variability of vegetation production. The discrepant patterns of growth peak response to climate and phenology reflect the distinct adaptability of the vegetation growth peak to climate change, and result in different carbon sink patterns over the study area. The study of growth peak could improve our understanding of vegetation photosynthesis activity over various land covers and its contribution to carbon uptake.

Sensibilité de la production herbacée aux aléas de la distribution des pluies au Sahel (Agoufou, Mali): une approche par modélisation

La forte variation du régime des pluies au Sahel est reconnue par tous. La phénologie de la strate herbacée dominée par des plantes annuelles suit ce cycle annuel en faisant alterner une courte saison de croissance et une longue saison morte. Le Gourma situé dans la bande sahélienne au Mali est une zone pastorale soumise à cette variabilité temporelle des ressources pastorales (eau et fourrage) liée au régime de la mousson Ouest africaine, et aux fortes variations interannuelles de la pluviosité. Cette étude a pour objectif d’évaluer la sensibilité de la production de la strate herbacée aux variations de la distribution intra-saisonnière des pluies au Sahel à travers le cas du site pastoral d’Agoufou. Les simulations ont été effectuées avec le modèle STEP (Sahelian Transpiration Evaporation and Production model). Les analyses reposent sur de simples permutations des pluies journalières enregistrées sur le site en 2010, réalisées de façon aléatoire sans modifier le total saisonnier ni les cumuls journaliers. Les résultats montrent que la relation entre le cumul des pluies saisonnières et les phytomasses herbacées mesurées en fin de saison masque des chutes de production intra-saisonnière liées aux stress hydriques, notamment au cours de la période de croissance rapide qui affectent la production saisonnière. Le modèle pourrait servir dans un système intégré d’alertes précoces pour anticiper les pénuries de fourrage fréquentes dans cette région.Mots clés : Production primaire, strate herbacée, variation pluviométrique, stress hydrique, modèle STEP. English Title: Sensitivity of herbaceous vegetation production to the variability of rainfall distribution in the Sahel (Agoufou, Mali): a modeling approachThe strong spatial and temporal variability of rainfall patterns in the Sahel is accepted by everybody. The phenology of the herbaceous layer dominated by annual plants follows this rhythm by alternating a short growing period with a long dormancy period. The Gourma region located in the Sahelian belt in Mali is a pastoral area subject to this temporal variability of resources (water and forage) linked to the rains regime. This study aims to assess the sensitivity of the herbaceous vegetation production to the variation of the intra-seasonal rainfall distribution in the Sahel through the case of the Agoufou rangeland site. The simulations were performed with the STEP model (Sahelian Transpiration Evaporation and Production model). The analyses were based on simple changes of rainfall height recorded on the site in 2010, carried out randomly without changing the seasonal total or the daily totals. The results show that the relationship between rainfall totals and the fall of the herbaceous mass conceal intra-seasonal production related to water stress especially during the period of so-called main growth can affect the seasonal production. The model could be used in an integrated early warning system to anticipate frequent forage shortages in this region.Keywords: Primary production, herbaceous layer, rainfall variation, water deficit, STEP model.

Tradeoff between the Conservation of Soil C Stocks and Vegetation Productivity in Temperate Grasslands

Grassland management affects ecosystem services such as the conservation of C stocks. The aim of this study was to analyze the relation between vegetation production and soil C stocks for a set of seven temperate grasslands of various productivity levels. We estimated vegetation production directly through measurements of aboveground biomass (>5 cm), stubble and root biomass, and indirectly via plant community functioning. Soil C stocks were measured for bulk soil (organic C, SOC) and hot-water-extractable C (HWC) of topsoil. Plant community functioning was characterized by community-weighted mean (CWM) traits and functional diversity index. Results show a negative relation between biomass production and SOCstock. The tradeoff between productivity and SOCstock could be linked to plant community functioning and particularly Leaf Dry Matter content (LDMCCWM) which appeared to be the most relevant descriptor of plant community functioning. High SOCstock could be associated to low productivity, conservative strategy (high LDMCCWM), low soil labile C content and grassland age. Our results show a strong direct effect of management and grassland age on plant community, which in turn affects plant tissue quality and subsequent organic matter mineralization. Old permanent grasslands appeared less productive but represent an occasion for C storage and thus global change mitigation.

Safety of repeated use of deep-level openings in Norilsk mines

The article discusses safe repeated use of deep-level openings in Norilsk mine for vegetable production and herb cultivation in special facilities. Farming on the field in the north and east of Russia either is restricted by a short warm period suitable for vegetation, or is impossible due to climate, while the glasshouse industry bears losses because of the power cost and other expenses. At the actual depth of mining in the Talnakh ore cluster, the mine air temperature may reach 40 Celsius degrees and higher, which offers comfortable condition for the implementation of R&D projects in biotechnologies. One the other hand, the ore bodies in the cluster are rockburst-hazardous, which means high probability of dynamic events with deformation and destruction of underground excavations. It is necessary to undertake the elaborated studies into geodynamic safety to select and validate installation sites for biotechnology objects. It is suggested to select deep-level installation sites for the production of vegetable crops AVK-15 with regard to the geodynamic zoning of the Norilsk ore cluster. Deeplevel vegetation production will become safe as a result, and new eco-friendly and adaptable technologies will be developed for the year-round cultivation of fresh vegetables and green at the low material inputs and power consumption per unit product.

Plant Disease Identification using C-Means and SVM Classifier

Agriculture is the backbone of India. In India 58% of people india are depends on agriculture. Vegetable are the most popular common crops in India. Many diseases are affected during the growing. To detect the vegetables plant leaf disease is more important because of fewer propensities. The vegetation production gets affected if correct care isn't taken. Image process is one in all upbringing technology that helps to resolve such problems with varied algorithms and techniques. Most of the diseases of vegetable plants detected at primary stages as they have an effect on leaves 1st. detective work the diseases at the initial stage on leaves can sure as shooting avoid close loss. During this project, we tend to area unit characteristic the sickness victimization image segmentation and also the SVM rule. to spot the pathological half in leaf, image segmentation is employed. And for classification of correct sickness, Multi-class SVM rule is employed. In the last stage of the disease, detection is recommended by the User for treatment. Automatic disease detection has many benefits to monitor and control the large fields to detect the disease automatically. By using the pesticide minimize the economic loss and identify the disease. This project is implemented by using Digital image processing and it can recognize the problems in crops from images, based on colors and shape to detect the disease automatically. We can rectify the problem fast and accurate manner. The image processing (Digital) technique is used to magnify the image. Here in this project, we are introducing the IoT based smart farming using the Raspberry PI and sensors with the image process. Here we will capture the images of tomato leaves with cam which is connected with raspberry pi that captured images will be sent to email id and that images are done using image processing in MAT lab software.

Quantifying hydrologic controls on local- and landscape-scale indicators of coastal wetland loss

Background and Aims Coastal wetlands have evolved to withstand stressful abiotic conditions through the maintenance of hydrologic feedbacks between vegetation production and flooding. However, disruption of these feedbacks can lead to ecosystem collapse, or a regime shift from vegetated wetland to open water. To prevent the loss of critical coastal wetland habitat, we must improve understanding of the abiotic–biotic linkages among flooding and wetland stability. The aim of this research was to identify characteristic landscape patterns and thresholds of wetland degradation that can be used to identify areas of vulnerability, reduce flooding threats and improve habitat quality. Methods We measured local- and landscape-scale responses of coastal wetland vegetation to flooding stress in healthy and degrading coastal wetlands. We hypothesized that conversion of Spartina patens wetlands to open water could be defined by a distinct change in landscape configuration pattern, and that this change would occur at a discrete elevation threshold. Key Results Despite similarities in total land and water cover, we observed differences in the landscape configuration of vegetated and open water pixels in healthy and degrading wetlands. Healthy wetlands were more aggregated, and degrading wetlands were more fragmented. Generally, greater aggregation was associated with higher wetland elevation and better drainage, compared with fragmented wetlands, which had lower elevation and poor drainage. The relationship between vegetation cover and elevation was non-linear, and the conversion from vegetated wetland to open water occurred beyond an elevation threshold of hydrologic stress. Conclusions The elevation threshold defined a transition zone where healthy, aggregated, wetland converted to a degrading, fragmented, wetland beyond an elevation threshold of 0.09 m [1988 North American Vertical Datum (NAVD88)] [0.27 m mean sea level (MSL)], and complete conversion to open water occurred beyond 0.03 m NAVD88 (0.21 m MSL). This work illustrates that changes in landscape configuration can be used as an indicator of wetland loss. Furthermore, in conjunction with specific elevation thresholds, these data can inform restoration and conservation planning to maximize wetland stability in anticipation of flooding threats.