Ecosystems worldwide are rapidly losing taxonomic, phylogenetic, genetic, and functional diversity as a result of human appropriation of natural resources, modification of habitats and climate, and ...the spread of pathogenic, exotic, and domestic plants and animals. Twenty years of intense theoretical and empirical research have shown that such biotic impoverishment can markedly alter the biogeochemical and dynamic properties of ecosystems, but frontiers remain in linking this research to the complexity of wild nature, and in applying it to pressing environmental issues such as food, water, energy, and biosecurity. The question before us is whether these advances can take us beyond merely invoking the precautionary principle of conserving biodiversity to a predictive science that informs practical and specific solutions to mitigate and adapt to its loss.
BRCA1 variants are extensively associated with increased risk of breast cancer. Early detection and screening of variants is still rare in developing countries. Here, we investigated six BRCA1 ...variants in 300 subjects from Pakistani population using tetra amplification‐refractory mutation system (T‐ARMS) PCR. Our results indicate significant association of BRCA1 variants rs8176237 (AA; OR 8.2, 95% CI 3.02–22.64, p < 0.0001), rs1060915 (CC; OR 4.29, 95% CI 1.94–9.48, p = 0.0003), and rs799912 (TT; OR 3.16, 95% CI 1.44–6.94, p = 0.004) with up to 8‐fold increased odds of breast cancer under recessive model. Furthermore, BRCA1 haplotypes AGCACG and AGCCCT were associated with up to 18% breast cancer cases (p < 0.05). Additionally, we found association of these variants with up to 11‐fold increased odds of benign breast tumors. Linkage disequilibrium (LD) block‐wise analysis revealed haplotypes GCAC and ATAC were associated with significantly increased risk. To our knowledge, this is the first study that identifies the association of these BRCA1 variants with breast tumors in Pakistani population. In conclusion, BRCA1 variants investigated in the present study are associated with high odds of benign‐ and malignant breast tumors. Studies with bigger sample size may help early detection and screening to reduce the odds of breast cancer.
How closely does variability in ecologically important traits reflect evolutionary divergence? The use of phylogenetic diversity (PD) to predict biodiversity effects on ecosystem functioning, and ...more generally the use of phylogenetic information in community ecology, depends in part on the answer to this question. However, comparisons of the predictive power of phylogenetic diversity and functional diversity (FD) have not been conducted across a range of experiments. To address how phylogenetic diversity and functional trait variation control biodiversity effects on biomass production, we summarized the results of 29 grassland plant experiments where both the phylogeny of plant species used in the experiments is well described and where extensive trait data are available. Functional trait variation was only partially related to phylogenetic distances between species, and the resulting FD values therefore correlate only partially with PD. Despite these differences, FD and PD predicted biodiversity effects across all experiments with similar strength, including in subsets that excluded plots with legumes and that focused on fertilization experiments. Two- and three-trait combinations of the five traits used here (leaf nitrogen percentage, height, specific root length, leaf mass per unit area, and nitrogen fixation) resulted in the FD values with the greatest predictive power. Both PD and FD can be valuable predictors of the effect of biodiversity on ecosystem functioning, which suggests that a focus on both community trait diversity and evolutionary history can improve understanding of the consequences of biodiversity loss.
•First study generated naturalized streamflow and assesses environmental flow for all tributaries of the Amudarya River.•The estimated environmental flow ranged from 25 to 46% of naturalized mean ...annual flow (MAF) for all tributaries.•Current environmental flow (2–5% of MAF) is extremely lower than the estimated one for the delta region.•Environmental conditions are severely damaged in the middle and lower reaches.
The Amudarya River (ADR) is the largest source of freshwater in Central Asia providing livelihood to millions of people by extracting water for agriculture. However, the over-exploitation has created some critical environmental issues. For example, almost no water for the delta and the Aral Sea, which was once the 4th largest lake in the world. The present study focused on the assessment of environmental flow requirements (E-flows) in the basin. However, the main challenges in the accomplishment were the unavailability of natural streamflow, which is necessary for E-flow assessment, and sparse and limited hydroclimatic data. A hydrologic model was configured to simulate naturalized streamflow using the meteorological data from the Climate Research Unit. Four hydrological methods (i.e., Tennant, low flow index (7Q10), flow duration curve analysis (Q90, and Q95), and flow duration curve shifting (FDCS)) and all-method mean were applied to estimate E-flows at 34 sites on all tributaries of the ADR. According to FDCS, 7Q10, Q90, and Q95, E-flows should be 46%, 37%, 30%, and 25% of naturalized mean annual flow (NMAF), respectively, and on average, it should be 35% of NMAF, assessed by the all-methods mean. For low-flow (October–March) and high-flow (April–September) months, E-flows were determined to be 20–30% and 40–98% of NMAF, respectively. E-flow evaluation with the current environmental conditions showed very serious concerns because no sites met the environmental flow requirements below Kerki. This study will be guidelines to improve the riverine ecosystem and for future sustainable development in the region.
Post-industrial era has witnessed significant advancements at unprecedented rates in the field of medicine and cosmetics, which has led to affluent use of pharmaceuticals and personal care products ...(PPCPs). However, this has exacerbated the influx of various pollutants in the environment affecting living organisms through multiple routes. Thousands of PPCPs of various classes—prescription and non-prescription drugs—are discharged directly into the environment. In this review, we have surveyed literature investigating plant-based remediation practices to remove PPCPs from the environment. Our specific aim is to highlight the importance of plant-bacteria interplay for sustainable remediation of PPCPs. The green technologies not only are successfully curbing organic pollutants but also have displayed certain limitations. For example, the presence of biologically active compounds within plant rhizosphere may affect plant growth and hence compromise the phytoremediation potential of constructed wetlands. To overcome these hindrances, combined use of plants and beneficial bacteria has been employed. The microbes (both rhizo- and endophytes) in this type of system not only degrade PPCPs directly but also accelerate plant growth by producing growth-promoting enzymes and hence remediation potential of constructed wetlands.
Industrial agriculture is responsible for widespread environmental
degradation and undermines the pursuit of human well-being. With a
projected global population of 10 billion by 2050, it is urgent ...for
humanity to achieve a more sustainable approach to farming and food
systems. This concise text offers an overview of the key issues in
sustainable food production for all readers interested in the
ecology and environmental impacts of agriculture. It details the
ecological foundations of farming and food systems, showing how
knowledge from the natural and social sciences can be used to
create sustainable alternatives to the industrial production
methods used today. Beginning with a discussion of the role of
agriculture in human development, the primer examines how
twentieth-century farming methods are environmentally and socially
unsustainable, contributing to global change and perpetuating
inequalities. The authors explain the principles of environmental
sustainability and explore how these principles can be put into
practice in agrifood systems. They emphasize the importance of
human well-being and insist on the centrality of social and
environmental equity and justice. Sustainable Food
Production is a compelling guide to how we can improve our
ability to feed each other today and preserve the ability of our
planet to do so tomorrow. Appropriate for a range of courses in the
natural and social sciences, it provides a comprehensive yet
accessible framework for achieving agricultural sustainability in
the Anthropocene.
Nitrogen (N) deposition is widely considered an environmental problem that leads to biodiversity loss and reduced ecosystem resilience; but, N fertilization has also been used as a management tool ...for enhancing primary production and ground cover, thereby promoting the restoration of degraded lands. However, empirical evaluation of these contrasting impacts is lacking. We tested the dual effects of N enrichment on biodiversity and ecosystem functioning at different organizational levels (i.e., plant species, functional groups, and community) by adding N at 0, 1.75, 5.25, 10.5, 17.5, and 28.0 g N m⁻² yr⁻¹ for four years in two contrasting field sites in Inner Mongolia: an undisturbed mature grassland and a nearby degraded grassland of the same type. N addition had both quantitatively and qualitatively different effects on the two communities. In the mature community, N addition led to a large reduction in species richness, accompanied by increased dominance of early successional annuals and loss of perennial grasses and forbs at all N input rates. In the degraded community, however, N addition increased the productivity and dominance of perennial rhizomatous grasses, with only a slight reduction in species richness and no significant change in annual abundance. The mature grassland was much more sensitive to N-induced changes in community structure, likely as a result of higher soil moisture accentuating limitation by N alone. Our findings suggest that the critical threshold for N-induced species loss to mature Eurasian grasslands is below 1.75 g N m⁻² yr⁻¹, and that changes in aboveground biomass, species richness, and plant functional group composition to both mature and degraded ecosystems saturate at N addition rates of approximately 10.5 g N m⁻² yr⁻¹. This work highlights the tradeoffs that exist in assessing the total impact of N deposition on ecosystem function.
•Significant (p < 0.01) correlation between monthly variation in groundwater level and water fluxes in Mu Us Sandy Land.•Groundwater level strongly decreased before 2011 but increased gradually after ...2011.•Increase in precipitation change plays a dominated role for the groundwater recovery.
Groundwater resources play a crucial role in vegetation restoration and ecological development in the northern part of the Loess Plateau. However, it remains unclear how the groundwater level has changed with the restoration of ecological environments in the last two decades in the region, where long-term groundwater observations are largely not available. This study reconstructed the groundwater level in this region from 2001 to 2020 by establishing relationships between the monthly surface water fluxes (precipitation, evapotranspiration, and runoff) and the observed change in groundwater level from 2018 to 2020 and extrapolating the relationships to the pre-2018 period. We found that the groundwater level strongly decreased before 2011 but increased gradually after 2011. Increase in precipitation change plays a dominated role for the groundwater recovery and increase in evapotranspiration plays a substantial role, despite secondary. Our result is probably unexpected, but provides insights for possible change in groundwater resources in the near future in the regions with large-scale ecological restoration.
Accurate assessment of vegetation dynamics provides important information for ecosystem management. Anthropogenic activities and climate variations are the major factors that primarily influence ...vegetation ecosystems. This study investigates the spatiotemporal impacts of climate factors and human activities on vegetation productivity changes in China from 1985 to 2015. Actual net primary productivity (ANPP) is used to reflect vegetation dynamics quantitatively. Climate-induced potential net primary productivity (PNPP) is used as an indicator of climate change, whereas the difference between PNPP and ANPP is considered as an indicator of human activities (HNPP). Overall, 91% of the total vegetation cover area shows declining trends for net primary productivity (NPP), while only 9% shows increasing trends before 2000 (base period). However, after 2000 (restoration period), 78.7% of the total vegetation cover area shows increasing trends, whereas 21.3% of the area shows decreasing trends. Moreover, during the base period, the quantitative contribution of climate change to NPP restoration is 0.21 grams carbon per meter square per year (gC m−2 yr−1) and to degradation is 2.41 gC m−2 yr−1, while during the restoration period, climate change contributes 0.56 and 0.29 gC m−2 yr−1 to NPP restoration and degradation, respectively. Human activities contribute 0.36 and 0.72 gC m−2 yr−1 during the base period, and 0.63 and 0.31 gC m−2 yr−1 during the restoration period to NPP restoration and degradation, respectively. The combined effects of climate and human activities restore 0.65 and 1.11 gC m−2 yr−1, and degrade 2.01 and 0.67 gC m−2 yr−1 during the base and restoration periods, respectively. Climate factors affect vegetation cover more than human activities, while precipitation is found to be more sensitive to NPP change than temperature. Unlike the base period, NPP per unit area increases with an increase in the human footprint pressure during the restoration period. Grassland has more variability than other vegetation classes, and the grassland changes are mainly observed in Tibet, Xinjiang, and Inner Mongolia regions. The results may help policy-makers by providing necessary guidelines for the management of forest, grassland, and agricultural activities.
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