Quantifying the connections—linkages between land-use and water in the Kathmandu Valley,Nepal

Land development without thoughtful water supply planning can lead to unsustainability. In practice, management of our lands and waters is often unintegrated. We present new land-use, ecological stream health, water quality, and streamflow data from nine perennial watersheds in the Kathmandu Valley, Nepal, in the 2016 monsoon (i.e., August and September) and 2017 pre-monsoon (i.e., April and May) periods. Our goal was to improve understanding of the longitudinal linkages between land-use and water. At a total of 38 locations, the Rapid Stream Assessment (RSA) protocol was used to characterize stream ecology, basic water quality parameters were collected with a handheld WTW multi-parameter meter, and stream flow was measured with a SonTek FlowTracker Acoustic Doppler Velocimeter. A pixel-based supervised classification method was used to create a 30-m gridded land use coverage from a Landsat 8 image scene captured in the fall of 2015. Our results indicated that land-use had a statistically significant impact on water quality, with built land-uses (high and low) having the greatest influence. Upstream locations of six of the nine watersheds investigated had near natural status (i.e., river quality class (RQC) 1) and water could be used for all purposes (after standard treatments as required). However, downstream RSA measurements for all nine watersheds had RQC 5 (i.e., most highly impaired). Generally, water quality deteriorated from monsoon 2016 to pre-monsoon 2017. Our findings reinforce the importance of integrated land and water management and highlight the urgency of addressing waste management issues in the Kathmandu Valley.     

A cross-scale impact assessment of European nature protection policies under contrasting future socio-economic pathways

Regional Environmental Change - Protection of natural or semi-natural ecosystems is an important part of societal strategies for maintaining biodiversity, ecosystem services, and achieving overall...     

Understanding and actioning BRE environmental assessment method: a socio-technical approach

The following research applies a socio-technical approach to an original study of the role of BRE environmental assessment method (BREEAM) in sustainable building practice. The primary objective is to gain insight into what facilitates and what weakens professional associations to implement a sustainability agenda in a building project. It focuses on understanding different sets of meaning which underlie engagement with BREEAM and how BREEAM is actioned. To do this, the research framework draws on social network analysis. However, this research does not consider that sustainable building is merely an outcome of planned action. Instead, sustainable building is seen to involve processes of engagement amongst different groups, technologies, materials and methods. Therefore, the conceptual framework adopted incorporates consideration of the materiality of sustainable building engagements, highlighting the relations between actors. Interviews with project professionals involved in a case study of a BREEAM Outstanding development provide the empirical basis for this work. This research will be of interest to scholars interested in socio-technical approaches to building development, environmental building assessment methods and sustainable building.     

Effects of reduced water quality on coral reefs in and out of no‐take marine reserves

Near‐shore marine environments are increasingly subjected to reduced water quality, and their ability to withstand it is critical to their persistence. The potential role marine reserves may play in mitigating the effects of reduced water quality has received little attention. We investigated the spatial and temporal variability in live coral and macro‐algal cover and water quality during moderate and major flooding events of the Fitzroy River within the Keppel Bay region of the Great Barrier Reef Marine Park from 2007 to 2013. We used 7 years of remote sensing data on water quality and data from long‐term monitoring of coral reefs to quantify exposure of coral reefs to flood plumes. We used a distance linear model to partition the contribution of abiotic and biotic factors, including zoning, as drivers of the observed changes in coral and macro‐algae cover. Moderate flood plumes from 2007 to 2009 did not affect coral cover on reefs in the Keppel Islands, suggesting the reef has intrinsic resistance against short‐term exposure to reduced water quality. However, from 2009 to 2013, live coral cover declined by ～50% following several weeks of exposure to turbid, low salinity water from major flood plume events in 2011 and subsequent moderate events in 2012 and 2013. Although the flooding events in 2012 and 2013 were smaller than the flooding events between 2007 to 2009, the ability of the reefs to withstand these moderate floods was lost, as evidenced by a ～20% decline in coral cover between 2011 to 2013. Although zoning (no‐take reserve or fished) was identified a significant driver of coral cover, we recorded consistently lower coral cover on reserve reefs than on fished reefs throughout the study period and significantly lower cover in 2011. Our findings suggest that even reefs with an inherent resistance to reduced water quality are not able to withstand repeated disturbance events. The limitations of reserves in mitigating the effects of reduced water quality on near‐shore coral reefs underscores the importance of integrated management approaches that combine effective land‐based management with networks of no‐take reserves.     

Assessing strategies to reconcile agriculture and bird conservation in the temperate grasslands of South America

Globally, agriculture is the greatest source of threat to biodiversity, through both ongoing conversion of natural habitat and intensification of existing farmland. Land sparing and land sharing have been suggested as alternative approaches to reconcile this threat with the need for land to produce food. To examine which approach holds most promise for grassland species, we examined how bird population densities changed with farm yield (production per unit area) in the Campos of Brazil and Uruguay. We obtained information on biodiversity and crop yields from 24 sites that differed in agricultural yield. Density–yield functions were fitted for 121 bird species to describe the response of population densities to increasing farm yield, measured in terms of both food energy and profit. We categorized individual species according to how their population changed across the yield gradient as being positively or negatively affected by farming and according to whether the species’ total population size was greater under land‐sparing, land‐sharing, or an intermediate strategy. Irrespective of the yield, most species were negatively affected by farming. Increasing yields reduced densities of approximately 80% of bird species. We estimated land sparing would result in larger populations than other sorts of strategies for 67% to 70% of negatively affected species, given current production levels, including three threatened species. This suggests that increasing yields in some areas while reducing grazing to low levels elsewhere may be the best option for bird conservation in these grasslands. Implementing such an approach would require conservation and production policies to be explicitly linked to support yield increases in farmed areas and concurrently guarantee that larger areas of lightly grazed natural grasslands are set aside for conservation.     

Aspergillus sclerotiorum lipolytic activity and its application in bioremediation of high-fat dairy wastewater environments

Oils and grease (O&G) have low affinity for water and represent a class of pollutants present in the dairy industry. Enzyme-mediated bioremediation using biocatalysts, such as lipases, has shown promising potential in biotechnology, as they are versatile catalysts with high enantioselectivity and regioselectivity and easy availability, being considered a clean technology (white biotechnology). Specially in the treatment of effluents from dairy industries, these enzymes are of particular importance as they specifically hydrolyze O&G. In this context, the objective of this work is to prospect filamentous fungi with the ability to synthesize lipases for application in a high-fat dairy wastewater environment. We identified and characterized the fungal species Aspergillus sclerotiorum as a good lipase producer. Specifically, we observed highest lipolytic activity (20.72 U g⁻¹) after 96 h of fermentation using sunflower seed as substrate. The fungal solid fermented was used in the bioremediation in dairy effluent to reduce O&G. The experiment was done in kinetic from 24 to 168 h and reduced over 90% of the O&G present in the sample after 168 h. Collectively, our work demonstrated the efficiency and applicability of fungal fermented solids in bioremediation and how this process can contribute to a more sustainable wastewater pretreatment, reducing the generation of effluents produced by dairy industries.

     

某典型农业活动区土壤与地下水有机氯农药污染健康风险评价

以长江三角洲某农业活动区为目标研究区域,分别采集研究区O～20 cm、20～40 cm、40～60 cm深度土壤样与浅层地下水样,分析该区有机氯农药六六六(HCHs)与滴滴涕(DDTs)在不同深度土壤至潜水含水层中的残留分布特征,并应用美国RBCA模型对研究区HCHs和DDTs进行健康风险评价.结果表明:在表层、第二层、第三层3个土层中β-HCH与DDE最大检出水平分别为50.28 μg· kg-1与60.35μg·kg-1、30.25μg·kg-1与30.29μg·kg-1、3.54 μg· kg-1与7.63 μg· kg-1,检出率分别为76.5％与69.8％、75.2％与65.2％、40.3％与30.5％,而该区浅层地下水中农药残留未检出.基于RBCA健康风险评价模型计算该农业活动区中HCHs和DDTs累加致癌风险值为4.7×10-5,致癌风险较小;HCHs和DDTs的平均浓度值和最大浓度值对应的非致癌健康风险均未超出US EPA安全阈值1.0,风险较低.     

长江干流近岸沉积物重金属的空间分布及风险评估

采集长江干流上、中、下游人口分布密集的主要城市江段、三峡库区等19个监测断面的近岸沉积物样品,分别分析了枯水期和丰水期沉积物样品中砷、汞、铜、铅、镉、锌和锰等重金属含量在长江干流上的分布特征.结果表明,枯水期,砷和铅在三峡库区寸滩断面含量最大,铜和汞在入江口含量最大.丰水期,长江干流最上游的两个监测断面汞、砷、铜、铅4种重金属含量均较低;三峡库区砷、铜、铅3种重金属总量均较大,汞含量也较高.依据相平衡分配法和沉积物污染指数法(SPI),选取铜和铅两项参数,对长江干流近岸沉积物质量进行风险评估,结果显示,长江干流19个监测断面近岸沉积物等级均为Ⅰ类,但入江口沉积物污染指数(SPI)值最大.     

0D/3D direct Z-scheme heterojunctions hybridizing by MoS2 quantum dots and honeycomb conjugated triazine polymers (CTPs) for enhanced photocatalytic performance

Herein, a novel direct Z-scheme photocatalyst was accomplished by hybridization of 0D MoS₂ quantum dots (MSQDs) and 3D honeycomb-like conjugated triazine polymers (CTP) (namely, CTP-MSQD). The unique 0D/3D hierarchical structure significantly enhanced the exposure of active sites and light harvesting property, while the formed p-n junction enabled the direct strong interface coupling without the necessity of any mediators. The optimized CTP-MSQD3 exhibited continuously increased visible-light-driven photocatalytic activity and strong durability both in Cr(VI) reduction and H₂ evolution, featured a rate of 0.069 min⁻¹ and 1070 µmol/(hr∙g), respectively, which were 8 times than those of pure 3D-CTP (0.009 min⁻¹ and 129 µmol/(hr∙g)). We believe that this work provides a promising photocatalyst system that combines a 0D/3D hierarchical structure and a Z-scheme charge flow for efficient and stable photocatalytic conversion.