High grazing pressure accelerates changes in community assembly over time in a long-term grazing experiment in the desert steppe of northern China.

Although numerous studies have shown that grazing gives rise to community succession from the communities or even species perspective, there is a lack of discussion about how grazing drives community assembly based on plant functional traits in a long-term experiment. We find different grazing intensities lead to temporal effects on trait-mediated multidimensional community assembly processes, including community-weighted trait mean (CWM), trait filtering, and trait distribution (divergence/convergence). CWM, trait filtering, and trait distribution of different traits transformed over the 16-year grazing experiment.

Does land use change decline the regional ecosystem health maintenance? Case study in subtropical coastal region, Fuzhou, China.

Regional environmental management aims to maintain or improve regional ecosystem health (REH) and prevent its degradation over time. In the context of rapid urbanization and global sustainability over the last two decades, has land use change resulted in a deterioration of REH? By using the improved REH framework model as Pressure-Vigor-Organization-Resilience-Service (P-VOR-S), this paper proposed Regional Ecosystem Health Maintenance (REHM) as a dynamic quantitative indicator of REH, and detected REHM as well as its response to land use change in the coastal city of Fuzhou, China during 2003-2018. The results showed that: (1) During 2003-2018, the average REH gradually decreased in spite of the 62.

Dry-season length affects the annual ecosystem carbon balance of a temperate semi-arid shrubland.

Semi-arid ecosystems have been shown to dominate over tropical forests in determining the trend and interannual variability of land carbon (C) sink. However, the magnitude and variability of ecosystem C balance remain largely uncertain for temperate semi-arid shrublands at the decadal scale. Using eddy-covariance and micro-meteorological measurements, we quantified the interannual variation in net ecosystem production (NEP) and its components, gross primary production (GPP) and ecosystem respiration (Reco, i.

Extracting Fractional Vegetation Cover from Digital Photographs: A Comparison of In Situ, SamplePoint, and Image Classification Methods.

Fractional vegetation cover is a key indicator of rangeland health. However, survey techniques such as line-point intercept transect, pin frame quadrats, and visual cover estimates can be time-consuming and are prone to subjective variations. For this reason, most studies only focus on overall vegetation cover, ignoring variation in live and dead fractions.

Phenotyping Flowering in Canola ( L.) and Estimating Seed Yield Using an Unmanned Aerial Vehicle-Based Imagery.

Phenotyping crop performance is critical for line selection and variety development in plant breeding. Canola ( L.) flowers, the bright yellow flowers, indeterminately increase over a protracted period.

Interannual variation in riparian vegetation cover and its relationship with river flow under a high level of human intervention: an example from the Yongding River Basin.

Riparian vegetation cover is significantly affected by a river's hydrological conditions. Especially in arid and semiarid areas, low flow will degrade riparian vegetation, and recent, intensive human activities in the Yongding River Basin have caused a sharp decrease in river flow. We analyzed interannual change in riparian vegetation, river flow effects, and land use on vegetation coverage using the 40 years (1977-2016) of remote sensing images and river flow, combined with 38 years (1980-2018) of land use data.

Identification of the Optimal Season and Spectral Regions for Shrub Cover Estimation in Grasslands.

Woody plant encroachment (WPE), the expansion of native and non-native trees and shrubs into grasslands, is a less studied factor that leads to declines in grassland ecosystem health. With the increasing application of remote sensing in grassland monitoring and measuring, it is still difficult to detect WPE at its early stages when its spectral signals are not strong enough. Even at late stages, woody species have strong vegetation characteristics that are commonly categorized as healthy ecosystems.

A Semi-Automated Method to Extract Green and Non-Photosynthetic Vegetation Cover from RGB Images in Mixed Grasslands.

Green (GV) and non-photosynthetic vegetation (NPV) cover are both important biophysical parameters for grassland research. The current methodology for cover estimation, including subjective visual estimation and digital image analysis, requires human intervention, lacks automation, batch processing capabilities and extraction accuracy. Therefore, this study proposed to develop a method to quantify both GV and standing dead matter (SDM) fraction cover from field-taken digital RGB images with semi-automated batch processing capabilities (i.

Understanding the factors associated with long-term reconstructed turbidity in Lake Diefenbaker from Landsat-imagery.

Turbidity affects a variety of aquatic ecosystem processes. Turbidity events are dominated by suspended sediment in many systems. High levels of suspended sediment in lakes can occur during periods of high inflows from turbid tributaries or suspension of sediment from lake beds.

Contributions of climate change to the terrestrial carbon stock of the arid region of China: A multi-dataset analysis.

Dryland ecosystems have been threatened in recent decades by rapid climate change. However, the effects of climate change and rising CO levels on the terrestrial carbon stock of the arid region of China remain unclear. In this study, we used three climate reanalysis datasets to drive an arid ecosystem model (AEM), which we used to assess uncertainties in spatial climate datasets.

Hourly photosynthetically active radiation estimation in Midwestern United States from artificial neural networks and conventional regressions models.

The relationship between hourly photosynthetically active radiation (PAR) and the global solar radiation (R s ) was analyzed from data gathered over 3 years at Bondville, IL, and Sioux Falls, SD, Midwestern USA. These data were used to determine temporal variability of the PAR fraction and its dependence on different sky conditions, which were defined by the clearness index. Meanwhile, models based on artificial neural networks (ANNs) were established for predicting hourly PAR.

Some insights on grassland health assessment based on remote sensing.

Grassland ecosystem is one of the largest ecosystems, which naturally occurs on all continents excluding Antarctica and provides both ecological and economic functions. The deterioration of natural grassland has been attracting many grassland researchers to monitor the grassland condition and dynamics for decades. Remote sensing techniques, which are advanced in dealing with the scale constraints of ecological research and provide temporal information, become a powerful approach of grassland ecosystem monitoring.

Remote sensing of ecosystem health: opportunities, challenges, and future perspectives.

Maintaining a healthy ecosystem is essential for maximizing sustainable ecological services of the best quality to human beings. Ecological and conservation research has provided a strong scientific background on identifying ecological health indicators and correspondingly making effective conservation plans. At the same time, ecologists have asserted a strong need for spatially explicit and temporally effective ecosystem health assessments based on remote sensing data.

Satellite remote sensing of harmful algal blooms (HABs) and a potential synthesized framework.

Harmful algal blooms (HABs) are severe ecological disasters threatening aquatic systems throughout the World, which necessitate scientific efforts in detecting and monitoring them. Compared with traditional in situ point observations, satellite remote sensing is considered as a promising technique for studying HABs due to its advantages of large-scale, real-time, and long-term monitoring. The present review summarizes the suitability of current satellite data sources and different algorithms for detecting HABs.

Mechanisms of functional connectivity: the case of free-ranging bison in a forest landscape.

Functional connectivity is a key determinant of animal distributions in heterogeneous landscapes. Patch connectivity depends on both patch preference and accessibility, but few studies have integrated habitat selection and movement analyses to gain a general understanding of functional connectivity. In this paper, we define functional connectivity by identifying which factors influence the choice of the patch that is visited next, the location from which animals leave the current patch, and the inter-patch trajectory.

Comparison of laboratory and field remote sensing methods to measure forage quality.

Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously.

Remote sensing of ecology, biodiversity and conservation: a review from the perspective of remote sensing specialists.

Remote sensing, the science of obtaining information via noncontact recording, has swept the fields of ecology, biodiversity and conservation (EBC). Several quality review papers have contributed to this field. However, these papers often discuss the issues from the standpoint of an ecologist or a biodiversity specialist.

Fusion hybrid of dendritic cells and engineered tumor cells expressing interleukin-12 induces type 1 immune responses against tumor.

Aims And Background: Dendritic cell (DC)-tumor fusion hybrid vaccinees that facilitate antigen presentation represent a novel powerful strategy in cancer immunotherapy. Preclinical studies have demonstrated that IL-12 promotes specific antitumor immunity mediated by T cells in several types of tumors. In the present study, we investigated the antitumor immunity derived from vaccination of fusion hybrids between DCs and engineered J558/IL-12 myeloma cells secreting Th1 cytokine IL-12.

Increased susceptibility of tumorigenicity and decreased anti-tumor effect of DC vaccination in aged mice are potentially associated with increased number of NK1.1+CD3+ NKT cells.

Aim: It is established that aging leads to declines in immune function. However, the mechanisms underlying remain poorly understood.

Methods: In this study, we compared the tumoriginecity of MO4 (ovalbumin-transfected) tumor cells, the efficacy of dendritic cell (DC) vaccination and cytotoxic T lymphocytes (CTLs), and the number of NK1.

Significant tumor regression induced by microencapsulation of recombinant tumor cells secreting fusion protein.

Implantation of microencapsulated engineered cells secreting molecules with antineoplastic properties into tumors is a novel approach to cancer gene therapy. In this study, we constructed an engineered tumor cell line, VkCk/RM4-TNF-alpha, which secreted RM4/TNF-alpha fusion protein containing the chimeric antitumor antibody, F(ab')2 (RM4), recognizing the tumor antigen TAG72, as well as the TNF-alpha moiety. The engineered cells were encapsulated into microencapsules.

A novel approach to tumor suppression using microencapsulated engineered J558/TNF-alpha cells.

Aim: Immunoisolation technology using microencapsulated nonautologous cells is a novel alternative approach to the treatment of cancer. The work was aimed on investigation of the effect of implantation of microencapsulates on tumor growth in vivo.

Methods: In this study, we constructed an engineered tumor cell line J558/TNF-alpha that secreted functional tumor necrosis factor-alpha (TNF-alpha) (2 ng/ml), and went on to encapsulate the engineered cells into microencapsules.

[Preliminary attempt at the speciation of 25-elements in the Chinese medicinal herbs].

Objective: To make an attempt at the multi-element speciation in the Chinese medicinal herbs by determining the concentrations of 25 elements in different extraction solutions.

Method: Firstly, five Chinese medicinal herbs (Buddleja officinalis, Dictamnus dasycarpus, Myristica fragrans, Albizia judibrissin and Inula japonica) from the same region of China were treated to obtain water-soluble phase, lipid-soluble phase and non-soluble phase by water extraction, organic solvent extraction and acid digestion, respectively. Secondly, Phytolacca acinosa, a Chinese medicinal herb collected from 9 regions of China, was extracted by 0% EtOH, 50% EtOH, 75% EtOH, 95% EtOH, respectively, referring the Chinese Pharmacopoeia.