Biodiversity and Impacts of Climate Change in Home Gardens

Home garden is a complex multi-functional land use system that combines multiple farming components of the homestead and provides environmental services, household needs, and employment and income generation opportunities to the households. Predicted climate changes have serious implications for crop and livestock yields particularly in tropical regions. Home garden may act as a cushion to the adverse climate shocks. There is dearth of in-depth study of home garden ecosystem in India. The authors have selected 100 households in Garhbeta-1 block, which is in the dry zone in the district of Paschim Medinipur in West Bengal, India for the study. The main objectives of the chapter include (1) identification of the key characteristics of the home garden, (2) assessing biodiversity in home gardens, (3) identifying the pattern of climate change from the household perceptions and the problems in home garden, and (4) the changes made in the home gardens.

Daily rainfall persistence over Sri Lanka

The spatial distribution of daily rainfall persistence is examined adopting Besson's persistence coefficient and using daily rainfall data for 15 consecutive years (1971-1985). The daily rainfall persistence coefficients have been studied separately for all the twelve months individually and for the whole year. Where January and February indicate the lowest rainfall persistence coefficients the period from October to December indicates the highest coefficients over Sri Lanka. Besides the monsoonal atmospheric conditions, the topography has a strong influence on the rainfall persistence distribution over space and time. The daily rainfall persistence coefficients record higher values in the wet zone then in the dry zone of Sri Lanka. Regression analysis shows a better linear relationship between mean length of wet spell~ and the daily rainfall persistence coefficients and the resultant final equation is y.4' =0.1093+0.1600+X M having the correlation coefficient of 0.721 which is significant at the 0.01% level.

Climate Change and Diseases of Plants and Animals

Home Garden is a complex sustainable land use system that combines multiple farming components of the homestead and provides environmental services, household needs, and employment and income generation opportunities to the households. Predicted climate changes have serious implications for crop and livestock yields particularly in tropical regions. Home garden may act as a cushion to the adverse climate shocks. There is dearth of in-depth study of home garden ecosystem in India. Authors selected 100 households in Garhbeta-1 block, which is in the dry zone in the district of Paschim Medinipur in West Bengal for this study. The main objectives of this chapter include: (a) identifying key characteristics of the home garden, (b) identifying the pattern of climate change from the household perceptions and the changes made in the home gardens. (c) identifying different diseases of plants and animals in home gardens in the study area (d) managing diseases of plants in home gardens, (e) identifying different problems/ constraints in home.

Yield formation by winter wheat as affected by sowing time

Исследование выполнено в 2019 и 2020 годах в зоне неустойчивого увлажнения Ставропольского края. Цель работы — изучить влияние сроков посева на рост, развитие, формирование урожайности и качества зерна озимой пшеницы (сорт Безостая 100). Схема опыта включала следующие варианты: 1) посев в III декаде сентября; 2) посев в I декаде октября; 3) посев во II декаде октября; 4) посев в III декаде октября. Изменение климата достаточно сильно сказывается на сроках посева. В условиях зоны неустойчивого увлажнения оптимальным сроком является III декада сентября. Высокий температурный режим при посеве в III декаде сентября способствовал быстрому прохождению фазы кущения, и к моменту ухода в зиму у 70% посевов наблюдалось перерастание, отдельные экземпляры растений озимой пшеницы перешли в фазу выхода в трубку, что повлияло на процесс протекания стадии закалки растений и зимостойкость в целом. В варианте с поздним сроком сева (в III декаде октября) растения не успели раскуститься и в зиму ушли в фазе двух-трёх листьев, что также повлияло на устойчивость растений к неблагоприятным факторам в период перезимовки. Растения озимой пшеницы, посеянные в I и II декадах октября, раскустились и ушли в зиму в фазе одного-трёх побегов, что обеспечило хороший процент перезимовавших растений. Проведённые исследования показали, что в среднем за 2 года наибольшая урожайность получена в вариантах с посевом в I и II декадах октября, при этом прибавка относительно оптимального срока посева составила 1,3–1,91 т/га. Разница между оптимальным сроком и посевом в III декаде октября составила 0,37 т/га. При этом наблюдалось снижение количества белка на 2,1%. При ранних сроках посева получено зерно III класса, тогда как при поздних сроках качество соответствовало IV классу. The investigation was conducted in the dry zone of the Stavropol region in 2019 and 2020. The aim was to analyze the effect of sowing time on winter wheat growth, development, productivity and grain quality (variety “Bezostaya 100“). The experiment included the following variants: 1) sowing in late September; 2) in early October; 3) in II decade of October; 4) in late October. Climate change significantly affects sowing time. Late September is considered to be an optimal sowing time under dry weather. High temperature in late September ensured active tillering stage. By winter 70% of plants grew too much, some of them were at shooting stage which influenced winter hardiness in general. Sown in late October plants did not reach their tillering stage which also affected their resistance to unfavorable conditions. Plants seeded in I and II decades of October were able to reach the tillering stage and effectively overwintered at the phase of 1–3 shoots. The highest productivity occured when seeding in I and II decades of October, yield increase amounted to 1.3–1.91 t ha-1. The difference in yield amounted to 0.37 t ha-1 between the optimal time and seeding in late October. Protein content dropped by 2.1%. Early sowing resulted in grain of III grade, while late seeding — IV grade.

The Influence of Habitat Changes on Elephant Mortality Associated with Human–Elephant Conflict: Identifying Areas of Concern in the North Central Dry Zone of Sri Lanka

Human–wildlife conflict (HWC) is becoming increasingly prevalent as human activity expands, and monitoring the impact of habitat quality on wildlife mortality related to HWC is critical for the well-being of wildlife and people. Using ten years of necropsies from free-ranging Asian elephants in the Northwestern Wildlife Region (NWR) of Sri Lanka, we quantified the effect of habitat quality on human–elephant conflict (HEC) (i.e., human-caused elephant mortality), hypothesizing that both artificial (e.g., forest cover loss) and natural (e.g., water availability, temperature) changes would be associated with elephant mortality. We collated necropsies from 348 elephants that died due to human activity from 2009 to 2018, comparing the results with data on forest cover loss, perennial water, rainfall, temperature, and human population sizes. Over the study period, we found that forest cover loss was significantly correlated with human-caused mortality in a district-specific manner. Similarly, access to perennial water and precipitation levels appeared to influence mortality, but not temperature, human population density, or percent land cover used for agriculture. We conducted emerging hot spot analyses to identify areas within the NWR that should be prioritized for protection, which included landscapes that are not currently protected (approximately 43% of the hot spots we identified). Similarly, areas that we identified as cold spots included many areas with minimal forest cover loss. Together, our results emphasize the impact that human activity can have on the measurable outcomes of HEC. We suggest that adaptive HWC management strategies that use retrospective analyses should inform any potential changes to the protection of vital wildlife habitats, such as the north central dry zone of Sri Lanka.

Prior Assessment of Variability in the Geotechnical Properties of Soils for Efficient Infrastructure Management

Advance assessments of variations in geotechnical properties of soils are invaluable in making a crucial judgment of geotechnical engineering projects. It could drive to reduce the number of field and laboratory tests so that efficient management design and construction of infrastructure project outputs can be achieved. In this study, we aim at assessing the geotechnical properties of residual, alluvial, marshy, coastal, and compacted soils within the wet and the dry zones of Sri Lanka. Plastic limit (PL), liquid limit (LL), shrinkage limit (SL), plasticity index (PI), liquidity index (LI), compression index (Cc), swell potential (SP), activity, natural moisture content (NMC) and SPT-N values were either extracted from reports or deduced from formulas and graphs. Wet zone marshy soils (My_W) show highest statistical means for PL (~23%), LL (~40%), PI (~16 %), SL (~20 %), LI (~ 1%), Cc (~ 0.200) and NMC (~ 35%), indicating poor engineering properties. Wet zone residual soils (Re_W) represent a wide range of direct correlations to the parent material. CH, OH, CL and SM soil groups for some My_W show high expansive, while, CL, Pt/CL, OL, SC, SM in My_W, CL, and SC in Re_W and CL in Dry Zone Alluvial Soils (Al_D) display medium expansive. The higher SPT-N values were recorded in the upper 6.00m and between 12.00-16.00m for the shell of earth dams (SED_D) in the dry zone, in contrast to Al_D soils representing higher N values for 6.00-12.00m. Except for marshy soils, no vertical variation for plasticity was observed in others. Since high to medium swell potential in the unsaturated zone is encountered within the upper 1.50m, attention should pay to the My_W. LL and PI of My_W were strongly correlated (R2 = 0.83) so that an equation PI% = -1.91 + (0.46*LL%) could be used to calculate PI. The results provide baseline geotechnical property variations for the five soils in Sri Lanka so that during planning, best-calculated assessment could be achieved which could minimize time and cost for crucial geotechnical investigations.