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Soil chemical properties plays a crucial role in crop yield. In this study, we evaluated the chemical properties of soils under three different cropping systems practiced for more than five years in Changunarayan municipality of Bhaktapur district of Nepal. The cropping systems includes- (i) cultivation inside polyhouse (Treatment A: polyhouse), (ii) paddy-wheat rotation (Treatment B: P-W), and (iii) paddy-wheat-vegetable rotation (Treatment C: P-W-V). Thirty-nine composite samples (13 replicates from each site) were taken from the area based on variation in landforms. Soil pH, organic matter (%), total nitrogen (%), available phosphorus (mgkg-1), and available potassium (mgkg-1) were evaluated for each sample. The study revealed that the soil pH was acidic and ranges between 4.71 and 5.39, organic matter (1.6-2.39%), total nitrogen (0.091-0.13%), phosphorus (4.48-29.24mg kg-1) and potassium (88.04-109.52 mg kg-1). A significant lower mean pH (4.71), and higher mean organic matter (2.39%), total nitrogen (0.13%) and available phosphorus (29.24 mgkg-1) were observed in cultivation under polyhouse. Incorporation of vegetable in paddy-wheat system gave significant (p

Climate change is an important driver of habitat contraction and the loss of biodiversity. Species distribution models (SDMs) are used to assess the impacts of climate change and to identify priority conservation areas. Conservation assessment of endemic keystone species can foster the conservation of forest ecosystems. The objectives of this study are: (1) to evaluate the potential impacts of future climate scenarios (RCP 4.5 and RCP 8.5) on the extents of the habitat of eight endemic montane conifer species under dispersal scenarios (full and limited) and (2) to estimate the percentage loss in the area of occupancy (AOO) of the target species based on projected habitat suitability in order to assess their extinction risks and identify priority conservation areas. Southwestern China is a global hotspot of conifer diversity and endemism. We used three ensemble-SDMs along with the International Union for Conservation of Nature’s Red List criteria to evaluate the impacts of climate change. Abies fabri, Abies fargesii var. faxoniana, Abies recurvata var. ernestii, and Picea neoveitchii are predicted to lose more than 90% of their AOOs under both the climate and dispersal scenarios. All of these species are predicted to become extinct or critically endangered except for Picea retroflexa and Abies squamata. It should be noted that while the changes in the AOOs changes were filtered for the current unsuitable man-made areas these predictions do not account for future land use changes. Stable and suitable habitats are promising tools for in-situ conservation planning. Moreover, future conservation actions should give full consideration to the pattern of climate and land use.

Nitrous oxide (N2O) measured simultaneously with di-nitrogen (N2) emissions from soils are greatly uncertain due to large temporal and spatial variations. This study aims to report N2O, N2, N2/N2O, 15N-N2O, wheat-maize annual grain yields, and yield-scaled N2O and N2O plus N2 emissions on the responses to different nitrogen (N) fertilizer rates in a winter wheat-summer maize cropping system. Furthermore, this study also seeks to determine controlling factors for N2O, N2, and N2/N2O emissions and significantly investigate the relationship between the soil-climate measured factors and 15N-N2O. Three N inputs and control treatments, 0, CK; 200, LN; 400, MN; and 600, HN kg N ha−1 year−1 were set since 1998. Direct measurement method has been used to quantify N2O and N2 emissions. Our results indicated that the effects of long-term N fertilization significantly increased N2O and N2 and also reduced N2/N2O emission ratios as described by exponential functions. Using structural equation modeling (SEM), NH4+, WFPS, NO3-, and DOC were revealed to be main controlling factors for N2O, while N2 by DOC, NO3-, WFPS, and temperature finally N2/N2O was positively related to temperature. Furthermore, the 15N-N2O was positively related to N2/N2O ratios, indicating that denitrification is the dominant process at the study site. The yield-scaled N2O emissions followed the order HM>MN>LN>CK, and they were 1.56, 1.47, and 1.07 times greater than CK, respectively. Total yield-scaled N2O plus N2 were in the order of CK>HN>MN>LN. N fertilization has shown strong impact not only on N2O, N2, and N2/N2O emissions but also on yield-scaled N2O and N2O plus N2 emissions. High agronomic nitrogen use efficiency (NUE), low yield-scaled N2O emissions, and low cumulative N2O plus N2 emissions were observed at 200-LN treatment, suggesting this rate to be an optimum and sustainable agricultural management practice with no significant crop yield reduction as compared to the current farmers’ practice of 400 kg N ha−1 year−1.

Aim As a prominent geographical distribution centre for the dark coniferous forests, mountains of Southwest China (MSWC) is experiencing an unprecedented warming trend, posing severe challenges to the survival of dominant fir (Abies) species. Although plant's migration ability is a prerequisite for its survival in changing environments, it has often been ignored in species distribution models (SDMs). This study aimed to quantify the magnitude and direction of range changes by the year 2080 for six dominant fir species, that is Abies recurvata, Abies faxoniana, Abies squamata, Abies ernestii, Abies forrestii and Abies georgei, with an emphasis on exploring the relationship between migration ability and projected distributions. Location The mountains of Southwest China. Methods We applied the Maximum Entropy (Maxent) algorithm to calibrate ecological niche models and to project the climatically suitable areas (CSAs) of each species under two emission scenarios (RCP 4.5 and RCP 8.5). Additionally, we delimited future species ranges by three migration scenarios (full-, no- and partial-migration scenarios). Results The simulations showed the distinctive responses of the six fir species to anthropogenic climate change (ACC). By 2080, the distribution areas of Abies recurvata were projected to decline only in the no-migration scenario but increase under the full- and partial-migration scenarios, while the other five species were projected to decline in the majority of emission x migration scenarios. Fir species in the southern region were predicted to be more vulnerable to ACC due to the larger losses in CSAs and a stronger effect of the partial-migration scenario on the newly colonized areas of this group. The studied species showed a simulated migration trend (northward and westward) to the interior Qinghai-Tibet Plateau under ACC. Main conclusions Benefits or losses for species under ACC depended on the geographical location, their ecological niches and migration abilities, which provide essential insights for a spatial conservation assessment of biodiversity hotspots in the future.

Understanding the factors driving the Quaternary distribution of Abies in the Tibetan Plateau (TP) is crucial for biodiversity conservation and for predicting future anthropogenic impacts on ecosystems. Here, we collected Quaternary paleo‐, palynological, and phylogeographical records from across the TP and applied ecological niche models (ENMs) to obtain a profound understanding of the different adaptation strategies and distributional changes in Abies trees in this unique area. We identified environmental variables affecting the different historical biogeographies of four related endemic Abies taxa and rebuilt their distribution patterns over different time periods, starting from the late Pleistocene. In addition, modeling and phylogeographic results were used to predict suitable refugia for Abies forrestii, A. forrestii var. georgei, A. fargesii var. faxoniana, and A. recurvata. We supplemented the ENMs by investigating pollen records and diversity patterns of cpDNA for them. The overall reconstructed distributions of these Abies taxa were dramatically different when the late Pleistocene was compared with the present. All Abies taxa gradually receded from the south toward the north in the last glacial maximum (LGM). The outcomes showed two well‐differentiated distributions: A. fargesii var. faxoniana and A. recurvata occurred throughout the Longmen refuge, a temporary refuge for the LGM, while the other two Abies taxa were distributed throughout the Heqing refuge. Both the seasonality of precipitation and the mean temperature of the driest quarter played decisive roles in driving the distribution of A. fargesii var. faxoniana and A. recurvata, respectively; the annual temperature range was also a key variable that explained the distribution patterns of the other two Abies taxa. Different adaptation strategies of trees may thus explain the differing patterns of distribution over time at the TP revealed here for endemic Abies taxa., All Abies species gradually receded from the south toward the north in the last glacial maximum (LGM). Abies fargesii var. faxoniana and A. recurvata occurred throughout the Longmen refuge, which was a temporary refuge only for the LGM, while the other two Abies taxa were distributed throughout the Heqing refuge. Different adaptation strategies may explain the different patterns of distribution of the four endemic Abies taxa.

Climate change and human activities can influence vegetation net primary productivity (NPP), a key component of natural ecosystems. The Qinghai-Tibet Plateau of China, in spite of its significant natural and cultural values, is one of the most susceptible regions to climate change and human disturbances in the world. To assess the impact of climate change and human activities on vegetation dynamics in the grassland ecosystems of the northeastern Qinghai-Tibet Plateau, we applied a time-series trend analysis to normalized difference vegetation index (NDVI) datasets from 2000 to 2015 and compared these spatiotemporal variations with trends in climatic variables over the same time period. The constrained ordination approach (redundancy analysis) was used to determine which climatic variables or human-related factors mostly influenced the variation of NDVI. Furthermore, in order to determine whether current conservation measures and programs are effective in ecological protection and reconstruction, we divided the northeastern Qinghai-Tibet Plateau into two parts: the Three-River Headwater conservation area (TRH zone) in the south and the non-conservation area (NTRH zone) in the north. The results indicated an overall (73.32%) increasing trend of vegetation NPP in grasslands throughout the study area. During the period 2000–2015, NDVI in the TRH and NTRH zones increased at the rates of 0.0015/a and 0.0020/a, respectively. Specifically, precipitation accounted for 9.2% of the total variation in NDVI, while temperature accounted for 13.4%. In addition, variation in vegetation NPP of grasslands responded not only to long- and short-term changes in climate, as conceptualized in non-equilibrium theory, but also to the impact of human activities and their associated perturbations. The redundancy analysis successfully separated the relative contributions of climate change and human activities, of which village population and agricultural gross domestic product were the two most important contributors to the NDVI changes, explaining 17.8% and 17.1% of the total variation of NDVI (with the total contribution >30.0%), respectively. The total contribution percentages of climate change and human activities to the NDVI variation were 27.5% and 34.9%, respectively, in the northeastern Qinghai-Tibet Plateau. Finally, our study shows that the grassland restoration in the study area was enhanced by protection measures and programs in the TRH zone, which explained 7.6% of the total variation in NDVI.

Drought is one of the major environmental stresses altering forest productivity. However, nutrient availability can modulate drought resistance. Phoebe zhennan (gold Phoebe) is a high‐quality timber‐producing but threatened tree species in China, facing serious anthropogenic disturbances and abiotic constraints that restrict its growth and development. However, little attention has been given to designing adaptive strategies for its management by evaluating the possible role of major nutrients, particularly nitrogen (N), on its morphological and physio‐biochemical responses under water stress. To evaluate these responses, a complete randomized design was followed to investigate the effects of two irrigation levels (well‐watered and drought‐stressed conditions) and N fertilization treatments (with and without N). Drought stress significantly affected the growth of seedlings, as indicated by impaired photosynthesis, pigment degradation, disrupted N metabolism, over‐production of reactive oxygen species and enhanced lipid peroxidation. Nitrogen supplementation under drought stress had remarkable positive effects on the growth through physio‐biochemical adjustments as shown by higher level of nitrogenous compounds and up‐regulation of N‐associated metabolic enzymes activities which might be due to N‐mediated improved leaf relative water contents and photosynthetic efficiency. In addition, N application reduced oxidative stress and membrane damage, and maintained a high accumulation of osmolytes. However, in well‐watered seedlings N fertilization significantly improved root biomass and net CO₂ assimilation rate suggesting high N‐use efficiency of the seedlings. These findings reveal that drought significantly affects the growth of P. zhennan, while N fertilization plays a crucial role in alleviating water stress damage by improving its drought tolerance potential at low metabolic costs. Therefore, N fertilization could be considered as an effective strategy for the conservation and management of P. zhennan in the face of future climate change.

Plants are either recognized to produce nitrous oxide (N

The 2015 Mw 7.8 Gorkha Nepal Earthquake had severely damaged buildings producing massive amount of debris. This paper assessed the amount of debris generated and construction waste during post-earthquake housing reconstruction in the earthquake most affected two districts. The study was carried out between April 2017 to December 2019, in Gorkha and Sindhupalchok districts of Nepal. The questionnaire survey were conducted in 17,814 households (Gorkha: 4896 and Sindhupalchok: 12,918) that were reconstructed after the earthquake. The sample household was selected randomly and the amount of debris and waste generated from each household was visually estimated. A z-test was performed to determine the quantity of debris and waste generated in each household at district as well as local administrative level. The result showed significant difference between the total amounts of debris generated in two districts - Gorkha (m = 17.03 m3/HHs; SD = ± 10.15) and Sindhupalchok (m = 21.61 m3/HHs; SD ± 8.92). Construction waste that was produced in construction sites in Gorkha and Sindhupalchok were 1.11 m3/HHs and 1.59 m3/HHs respectively. Proper management of debris and waste was lacking due to the absence of policies and guidelines on debris and waste in Nepal. However, individuals reused 57.96% of generated debris for housing reconstruction. The study recommends for preparation of debris and waste management plan for the future reconstruction activities.

Background: We aimed to characterise the geographical distribution of Sorensen-based multi-site dissimilarity (beta(sor)) and its underlying true turnover (beta(sim)) and nestedness (beta(sne)) components for Chinese Lauraceae and to analyse their relationships to current climate and past climate change. Methods: We used ensembles of small models (ESMs) to map the current distributions of 353 Lauraceae species in China and calculated beta(sor) and its beta(sim) and beta(sne) components. We tested the relationship between beta(sor), beta s(ne) and beta(sim) with current climate and past climate change related predictors using a series of simultaneous autoregressive (SAR(err)) models. Results: Spatial distribution of beta(sor) of Lauraceae is positively correlated with latitude, showing an inverse relationship to the latitudinal alpha-diversity (species richness) gradient. High beta(sor) occurs at the boundaries of the warm temperate and subtropical zones and at the Qinghai-Tibet Plateau due to high beta(sne). The optimized SAR(err) model explains beta(sor) and beta(sne) well, but not beta(sim). Current mean annual temperature determines beta(sor) and beta(sne) of Lauraceae more than anomalies and velocities of temperature or precipitation since the Last Glacial Maximum. Conclusions: Current low temperatures and high climatic heterogeneity are the main factors explaining the high multi-site beta-diversity of Lauraceae. In contrast to analyses of the beta-diversity of entire species assemblages, studies of single plant families can provide complementary insights into the drivers of beta-diversity of evolutionarily more narrowly defined entities.

Studying the pattern of species richness is crucial in understanding the diversity and distribution of organisms in the earth. Climate and human influences are the major driving factors that directly influence the large‐scale distributions of plant species, including gymnosperms. Understanding how gymnosperms respond to climate, topography, and human‐induced changes is useful in predicting the impacts of global change. Here, we attempt to evaluate how climatic and human‐induced processes could affect the spatial richness patterns of gymnosperms in China. Initially, we divided a map of the country into grid cells of 50 × 50 km2 spatial resolution and plotted the geographical coordinate distribution occurrence of 236 native gymnosperm taxa. The gymnosperm taxa were separated into three response variables: (a) all species, (b) endemic species, and (c) nonendemic species, based on their distribution. The species richness patterns of these response variables to four predictor sets were also evaluated: (a) energy–water, (b) climatic seasonality, (c) habitat heterogeneity, and (d) human influences. We performed generalized linear models (GLMs) and variation partitioning analyses to determine the effect of predictors on spatial richness patterns. The results showed that the distribution pattern of species richness was highest in the southwestern mountainous area and Taiwan in China. We found a significant relationship between the predictor variable set and species richness pattern. Further, our findings provide evidence that climatic seasonality is the most important factor in explaining distinct fractions of variations in the species richness patterns of all studied response variables. Moreover, it was found that energy–water was the best predictor set to determine the richness pattern of all species and endemic species, while habitat heterogeneity has a better influence on nonendemic species. Therefore, we conclude that with the current climate fluctuations as a result of climate change and increasing human activities, gymnosperms might face a high risk of extinction., China is one of the global biodiversity hot spot and an important ecological region to study the distribution of gymnosperms including endemic species. Here in this study, we try to evaluate the role of environmental‐ and human‐induced variables in determining the spatial pattern of species richness of gymnosperms. Our findings support that spatial richness pattern of all species of gymnosperms in China is mainly favored by climatic seasonality while energy–water and habitat heterogeneity variables have profound effect on endemic and nonendemic species, respectively.

Central Nepal has long history in the field of botanical investigation in contrast with different parts of the nation. Nevertheless, the present study area (Manaslu Conservation Area) is still under-explored. The present floristic study was carried out with the aim of fulfilling this gap by giving particular attention on flowering plants and their documentation. Two field visits were directed in May-June 2012 and September-October 2012 in two unique seasons with a specific end goal to gather plant samples of both seasons. On the contrary, herbarium specimens were prepared and later identified at Tribhuvan University Central Herbarium (TUCH) and National Herbarium and Plant Laboratory (KATH). The present study uncovers the presence of 276 species of flowering plants belonging to 78 families and 200 genera of which 63 families belong to dicotyledons and 15 families belong to monocotyledons. Among these, 17 species (6.15%) of climbers, 178 species (64.49%) of herbs, 58 species (21.01%) of shrubs and 23 species (8.33%) of trees are found. Economically important flowering plants comprise about 156 species where 75 species are used as medicine, 29 species as fuel wood, 23 species as fodder, 29 species are edible, 6 species are for religious purpose, 5 specifically for construction purpose, 10 for ornamental and 13 species reported to have miscellaneous uses. MCA accounts to 9 flowering plant species for research and development and agro-technology development and 12 species are listed under IUCN and CAMP threatened categories. MCA and its affinity are likewise house to 10 endemic flowering plants. As from the study it can be inferred that Manaslu Conservation Area (MCA) is a treasure hub of flowering plants that not only represent its economic importance rather it is also a house to threaten and endemic flowering plants. Thus, proper management plans must be implemented for the conservation of resources in MCA.

The present study analyzes the information and perception of the local community of Samagaun VDC, Manaslu Conservation Area Project (MCAP) regarding Dactylorhiza hatagirea (D. Don) Soo (Orchidaceae). We assessed the local peoples’ perception on its population status, its availability, factors causing its decline and management practices of this terrestrial orchids. A pre-designed questionnaire was used to gather information targeting the age group between 25 and 60 years (n = 75, 45 male and 30 female). Most of the informants (76%) believe that the abundance of this orchid is declining. Over grazing of domestic animals, over harvesting and lack of awareness among the local community were determined to be the major causes of decline of D. hatagirea in the study area. Protection measures as prescribed by the informants were control grazing, raising awareness among the individuals and sustainable harvestings for the long-term conservation of the species. Systematic management plans that incorporate the participation of local individuals and prioritization of their views will be applicable for the proper conservation of the species.

Water and poverty interface is strongly interconnected and a robust assessment of water stress is crucial to identify needy areas and develop appropriate intervention for poverty reduction. Water Poverty Index (WPI) provides an interdisciplinary tool to assess water stress by linking physical estimates of water availability with socio-economic drivers of poverty. This study presents an application of Water Poverty Index (WPI) to estimate and compare the level of water stress in 27 districts of Koshi River Basin in Nepal. Based on data availability, relevance to the study area and review of literatures, 12 indicators were selected under five key components outlined by WPI. The study result shows medium-low degree (WPI = 54.4) of water poverty in the Koshi River Basin in Nepal. The WPI score varies widely (from 49.75 to 69.29) along the districts and it was found that districts in Tarai regions and urban areas were more water stressed compared to the districts in mid-hill and high-hill regions. Priorities for intervention must be given to the districts in Tarai regions and urban areas with a low WPI score, explicitly on the sector regarding access to water and sanitation to address water poverty in the basin.

The distribution of forests can be hindcast or forecast when robust data and validation proofs are available. Distribution consequences for temperate coniferous forests during the Quaternary and future climatic fluctuations are little understood in China. Temperate coniferous forests are subdivided into two types where Pinus, Keteleeria, Tsuga and Cupressus species characterize the warm forests while Abies, Picea, Larix and Juniperus species characterize the cold forests. Both forest types were investigated using 12,675 unique records in the MaxEnt model to infer distribution patterns during six time periods: the present time, mid-Holocene, Last Glacial Maximum, Last Interglacial and the near- and far-future (2050, 2070). The results showed that the mean temperature of the driest quarter, followed by the temperature annual range and the precipitation of the warmest quarter were the most important variables controlling forests distribution. Suitable areas capable of supporting the presence of warm coniferous forests were highly contracted during the Quaternary; meanwhile, the cold coniferous forests expanded westwards from the last glacial maximum through the mid-Holocene to the present. The predicted future distributions showed a significant range-shift of warm forests northeastwards in response to climate change while cold coniferous forests are expected to migrate towards the Tibetan Plateau. Under increased global warming, the bioclimatic variables of the past and future periods were used as ecological indicators for the identification of areas showing “climatic stability”, and predicted to be refugia for coniferous forests and as good tools for conservation planning in Sichuan and the Hengduan-Tibetan migration corridor.

Dactylorhiza hatagirea (D. Don) Soo, commonly known as “Panchaunle”, is an important medicinal plant species distributed throughout the Himalaya region. The present work was conducted in order to assess its availability in natural habitats because of its medicinal properties, cultural significance and declining population density. The work focused primarily on its ecological features and conservation status. The density of D. hatagirea was found to be 2.18 individuals·m-2 with frequency and abundance being 81.81% and 2.67 individuals·m-2, respectively. We considered grazing, trampling, number of cattle and distance to settlement as anthropogenic factors. While grazing and trampling were shown to have a significant, negative impact on population density, we observed no significant change in the number of the species with respect to number of cattle and distance to settlement. We conclude that the species is threatened and that anthropogenic factors have a significant effect on its habitation in the study area.

Organophosphate and –phosphonates and their thiol derivatives are often used in agroindustry as herbicides and insecticides, but their potential off-targets in the plant and their consumers are poorly investigated. Here, we use competitive Activity-based Protein Profiling (ABPP) of serine hydrolases (SHs) to detect targets of these agrochemicals and other compounds in Arabidopsis thaliana. Using broad-range and specific probes, and by overexpression of various SHs in planta, we are able to confirm eight SH-compound interactions, including selective inhibition of carboxylesterase CXE12, prolyloligopeptidase, methylesterase MES2 and tripeptidyl peptidase TPP2. These observations can be used for the design of novel probes and selective inhibitors and may help to assess physiological effects of agrochemicals on crop plants.